Corn Nication Ourna O the Odio Ociety of Great Britain

June 1978 corn nication ourna o the odio ociety of Great Britain

UoS AMSAT-

The University of Surrey AMSAT telecom mand centre antenna mounting on the tower above the radio room of the university. An article on the telecom mand centre is published in this issue NE W FRO M atronics

Introducing the most comprehensive R.T.T.Y. TER MINAL UNIT you can, or indeed need ever buy-the Catronics CT100 Inputs for: Outputs for: Audio FSK signal in V.D U. or other TTL compatible equip ment Data in from V.D.U. (e.g. G3PLX) TTY Magnet - single or double current TTY Keyboard or Tape Reader AFSK to drive Transmitter Featuring a unique digitally controlled 'Autoprint circuit which is a superior replacement for the 'Antispace' and Autossart facilities found on some other terminal units The terminal will ignore most CW and phone signals but will respond to a correct RTTY signal. Tuning correctly into an RTTY signal is made simple with a single 'correctly tuned' LED plus an additional 'Mark frequency' indicator The FSK demodulator circuit utilises a special 'state-of -the-art' system to give excellent performance and stability at low cost The demodulator is set to decode signals within 75Hz of nominal frequency ie .1200-1350Hz for space and 1370-1520Hz for mark, when in narrow shift position The teleprinter interlace unit incorporates electronic 'de-bounce' circuitry to eliminate spurious switching from the Keyboard The loop supply is protected by a separate fuse and is suitable for driving all single current and double current magnets known to be available.

Units are es follo ws. CT100. Receive only RTTY Terminal Unit housed in attractively styled meter Units CT101 and/or CT102 may be added to the basic unit CT100 by the cabinet approx 9 by 7 by non with integral mains power supply input sockets customer al a later date if required for AFSK and TEL Output sockets for TTL drive to VDU VAT inclusive prices ate as follows CT101. Hu.stabany AFSK oscillator for transmission purposes Output socket CT100, 1/2 Complete Terminal Unit £88 00 from oscillator suitable for driving high or tow impedance microphone circuits CT100 Receive only Unir £71 00 CT102 Teleprintei interface unit input socket for Keyboard ni Tape reader II ordered II on:feted Output socket for Printer Magnet with CT100 separately Units may be combined e g a complete terminal unit loi reception and CT101 AFSK Oscillator £8.00 £12.30 transmission with facilities foi connection to Teleprinter is decroned C1-100 ,1 .7 CT102 Teleprintei Interlace £9.00 £13 70 Pius delivery charge f 3 00 rsecurrcoo AMATEUR RADIO VHF BULK BUYING GROU COMMUNICATIONS G3PLX RTTY VIDE O DISPLAY UNIT k (April 1977 Rad Corn) NO W PUBLISHED Co mplete Kit (excluding modulator, keyboard and the SPRING 1978 edition P.S.0 ). £77.15 which includes articles on Set of printed circuit boards £14.85. Veroboards also Preamp for 2m and 70cm available a/ £4.30 each. Set of c.s including program med 70em FM Transceiver (Part 4) 74188s. £56 15; 2513. £8.50; AY5-1013, £6.25; Filters for 23cm. 13cm and 9cm 2102-1, £2.85, SN74188. £3.40 each or ready pro- SHF Transmit Converter gram med £8.20 per parr 7M Hz Xtal. £3.25. Loop Vagi Antennas Flashing cursor kit £7.70 C M OS Circuits etc. etc Diode Matrix kit £11.50 Send Cl 25 for a copy of this edition or £4 50 for co mplete NOTE regarding PRO M program The PCB s and programmed PRO Ms supplied by us make use Dl a slightly different piogiani sequence resulting in 1978 volu me different pin connections to those published in the "Red Corn' aeticle Whilst Also 1977 subscription. £4 50 constructors buying PRO Ms and PCBs horn us will have rio difficulty Mose Producing then own PCBs or having PRO Ms programmed elsewhere should VHF CO M MUNICATIONS is the English language edition of the note this important difference A detailed modification sheet is available with German publication LIKW•SERICHTE, a quarterly amateur radio the PCBs magazine especially catering for yht/uhfishf technology li is G3TD7 FM 'BLACK BOX' published in spring, summer, autumn and winter. (A s March Rad •. Most components available— s a e for All special components required for the construction of the list described equipment, such as printed circuit boards, coil formers. semiconductors and crystals, as well as complete kits, are available M ULTIM O DE 1600 TR A NS CEIVER for despatch direct from Germany Many of the printed circuit Special price for complete kit. £210.00 boards, in addition to a few selected kits, are stocked in the UK. A Receive only kit also available. £1138.00 price list of kits and materials is available - send SAE for your copy PCB £12.90; 0C1246AX f.31.50; less carrier awls £27.50. XF9-E. ORDERS TO VHF COM MUNICATIONS AT ADDRESS BELO W f27.00: XF9 Aii1 £25.30. 85-45kHz Xtal, f3.00: 400es delay line, 0,70: MO108 £7.65; RS12v Relay £2.25. MiniKit 1 (containing all the above) £147.00 All prices include vrtur but please add minimum of 30p for post and MiniKit 2 (semiconductors) £54.50 or £29 85 eeretvr oniy packing MiniKit 3 R.», and C s £19 55 DEPT. 806, C O M M U NIC A TIO NS HO USE, 20 W ALLIN G T O N SQU ARE, W ALLIN G T O N, SU R RE Y SM6 8RG Tel: 01-669 6700 Open 9am to 5.30p m Mon to Fri. 9am to 1p m Sat. Closed for lunch 12.45 to 1.45p m EDITOR A. W. Hutchinson

Editorial assistant radio Mrs M. J. Collins communication Draughtsman D. E. Cole

Secretary June 1978 Volume54 No6

Mrs J. D. Brown C O NTE NTS 484 Current comment. QTC

486 The diagrammatic representation of radio signals— D. M. Cloke, Contributions (including Members' Ads) and all G4BMO correspondence concerning the content of Radio Communication should be addressed to: 491 New products

The Editor, RSGB, 492 A simple 10Gliz receiver with transmitter option —D. Evans. 88 Broomfield Road, G3RPE, and C. Suckling. G3WDCi Chelmsford, Essex CM1 1SS 495 Modifications to the Yaesu FR5OB receiver—E. ElsIcy. G3Y UQ

Tel 0245 84938 497 An afterburner for the G3TDZ fm black box—J. R. Hey. Tech(CEI). MSERT. G3TDZ Office hours: 0830-1630 498 The University of Surrey ANISAT telecommand centre— M. Sweet- ing. BSc, G3Y10 Correspondence concerning the distribution of the journal and all other Society matters should be 501 Microwaves—Charles Suckling. Ci3WDG addressed to: 502 Visiting the USA as an amateur radio operator--Bill Johnston. RSGB Headquarters, N5KR 35 Doughty St, 504 Observing radio satellites—P. T. Greed. G3MQ D London WC1N 2AE 506 Technical topics—Pat Hawker. G3VA Tel 01-837 8688 512 The month on the air -John Allaway, G3EK M Office hours: 0915-1715 515 HI; propagation study. Propagation predictions

516 4 — 2 — 70—Graham Knight. GM8FFX AD VERTISIN G 519 SWL. news—Bob Treacher, BRS32525 Advertising, other than Members' Ads, should be sent to: 520 SSTV scene—P. Burnett. G4BLL

Mr C. C. Lindsay, 521 White Rose Rally 1978 2 Leyburn Gardens, 522 Election of RSGB Regional Representatives. Croydon, Election of RSGB Area Representatives Surrey CRO 5N L

Tel 01-686 5839 523 Council proceedings 524 Your opinion. Obituaries. Looking ahead

525 RSGB slow morse practice transmissions EDITORIAL PA NEL 526 Contest news J. P. Hawker, G3VA R. F. Stevens, G2BVN 531 Contests calendar. Mobile rallies calendar. Special event stations

532 Members' ads

Radio Com munication is published by The Radio Society of Great Britain as its official journal on the first Thursday of each month and is sent free and post paid to all me mbers of the Society

20,286 copies per Closing date for contributions ABC issue average unless otherwise notified: ©RADIO SOCIETY OF «vane o• 1. . 41 circulation in 1977 4th of month preceding month of publication GREAT BRITAIN 1978 South Midlands ESTABLISHE D 1958 -20 YEARS YAESU - the world's leading manufacturer S.M.C.- the largest Yaesu UK distributor Our two-year guarantee and a free "24 hour" Securicor service are but a phone call away

N E W DE L U X E G E N E R A L CO V E R A G E RE CEI V E R The FR G7000 is a digital readout, to 1k Hz, general coverage receiver which inclusively covers 250kHz to 30M Hz. The receiver is sensitive (0.7pV for 10dB s/N) and very stable. Selectivity is switchable: .±1.5kHz for C W/SSB and ±3kHz (@-6db) for A M. A digital clock is incorporated (sellable to local and GMT times) with a relay timer circuit (for switching on tape recorder etc). Write for data sheet now. Ex-stock this month. F R G7000 Digital Receiver £306 VAT. YH55 Headphones £8.75 I VAT

F R G 7. A N A L O G U E O R S M C DI GI T A L RE A D O U T Tho FRG7 is a general coverage solid-state receiver with specifications unparalleled in its price range It uses a Barlow Wadley Triple-mix, drift cancelling loop for continuous, spin-tuned coverage of 0-5 to 30MHz. The receiver is sensitive (025pV for 10dB. S + N/N ( SSB ) and stable with AM. SSB and CW modes catered for A three-position audio filter. RF attenuator, dial lamp conservation switch, recorder and phone sockets are fitted, ti is mains powered. but should the supply fail or portable operation be required eight dry cells are automatically switched in The U K. sales of many thousand FRG7's last year amply demonstrates the outstanding value and enormous versatility of the unit with applications In Amateur (Fes' Rx or standby). SWL (Amateur and FICI..) or (or less demanding The SMC. full specification, internally mounted professional applications. counter (easily installed in existing receivers) FRG7 Analogue £164+ VAT SMC Counter £50.004 VAT provides: a 100Hz readout (100 fold improvement), flashing ± digit (to indicate VFO over. FR G7 Digital £217 r VAT YH55 Headphones £8.75 4 VAT range) and adjustable gate time.

T H E FR1 01 C O M M U NI C A TIO N S RE C EI V E R S The FR101D (deluxe) wide coverage )23 [from 1-5MHz] 500kHz bands 4- 4 and 2 metres) receiver. Analysis of the signal path shows. 0- 20dB switchable attenuator, two section permeability tuned input filter, Mosfet R.F stage and mixer (crystal controlled), three section top coupled bandpass filter, no gain at first IF. IC balance mixer, 20kHz wide crystal filter, shunt diode noise blanker, single FET buffer stage. AM. CW or SSB (F1TTY) filter, appropriate detector and audio stage. Add to this, two excellent VHF converters, squelch. FM detector, 1kHz readout, excellent stability. TX monitor control, crystal control facility. switchable AGC nansceive capability (FT or F L101) and that digital readout options are available of this (de-luxe) or the standard (less the plug•in optionals of converters, broadcast band crystals. filters etc). FR101S Standard Receiver £372.50+ VAT FR101 Deluxe receiver £465.00+ VAT

FR101SD Standard Digital £453.50 VAT FR101 DO Digital Deluxe £541..00+ VAT

F O R V H F M O BILE T H E FT227 R FR O M Y A E S U The new FT227R uses a "single knob" tuned digital synthesizer employing a photoelectric sensor ci an optical coupled system which eliminates both noisy, unreliable rotary switches, and crystal banks. Full coverage of 2 metres in 5k Hz divisions with a ± 600k Hz shift plus a memory feature which permits recall of any entered frequency or particular offset. Bright large, digital readout gives unequivocable readout of the frequency in use. The receiver offers e I N (for 20dB S + N/N) sensitivity into a _t 6kHz (at 6dB) bandwidth whilst maintaining a remarkable immunity to overload and image problems The 20YV DC input transmitter features Hi/Low power outputs. AFP tone burst on repeaters and an out of band inhibition trip. etc. EX STOCK £191.00 + VAT. FT227R

R E M E M B E R S M C FT227 R's H A V E FU LL Y A U T O T O N E B U R S T O N RE PE A T E R SHIF T O N L Y.

T H E FT223. 2 m LO W CO S T F M T R A N S CEI V E R

The FT223 is an FM transceiver operating on 23 crystal controlled channels (or by external VFO) across 144 to 148MHz. For mobile uses it is safe; illuminated; meter (RX 'S' and TX out) and main dial (when Crystal up) LED's indicate, squelch open, high 10W or tow 1W operation, on air, or if the special frequency is selected. Housed in heavy metal case and supplied complete with mounting bracket cables. connectors, microphone. etc.. it is equally at home as a compact (7" x 23' (T).81- (10')) base station with a 12V PSU, (0 45A RX, 1-2A LTX, 2-3A HTX) The dual conversion receiver is sensitive (mosfet RF and mixer), and selective, (12kHz at 6dB) delivering 2W to the internal e or an external 41) speaker. £139.50, 3 crystal pairs; £152.50, 8 crystal pairs ( +VAT12%)

FT223 FOR NE W 23 PAGE STOCK LIST. YAESU CATALOG UE. Etc. (44) S.A.E. or 30p STA MPS

A G E N T S

SOUTH MIDLANDS COMMUNICATIONS LTD. G3ZUL Stourbridge (038431 5917 OSB ORNE ROAD, TOTTON Head Office, Showtooms G MBDOX Dunblane (07861 822212 SOUTHA MPTON. SO4 4DN Cables: Aerial Southampton GI3 W WY Tandragee (0763) 840656 Hours of business 4-TuL Telex : 477351 SIVICO M M G G W3TIVIP Pontybodkin (035287) 846 DAY 9-5.30; 9-12.30 Saturday Tel: Totten (04216) 7333 (3 lines) G W3TIVIP Pontybodkin (035287) 324 EVE

R A DIO CO M M U NICA TIO N June 1978 462 Communications Ltd OF PROFESSIONAL EXPERIENCE \e/ YAESU NEW MULTI MODE 144MHz TRANSCEIVER AND MORE \ I

Based upon the extremely popular FT221, Yaesu proudly present the top line multi mode 2 metre transceiver. Super accurate mode sensitive 100Hz digital readout, 10W of AM, 25W of FM (continuously variable) and even more power on SSB. Repeater up-down 600kHz and aux shift. 11 crystals control positions (per 1 MHz band) and memory facility.

FT225R. £470.00 FT225RD £506.50 Counter £57.75 Me mory £84.50 All prices are VAT exclusive. EX-STOCK THIS MONTH

THE FT221R —A MULTI M O DE FRO M YAES U

The FT221R' The multimode USE, LSB. AM. FM, CW (with semi-break in and side tone). 2m transceiver offering the choice of phase locked VFO or 44 crystal channels, simplex or repeater (600Hz up and down shifts), with unique -double push - auto tone burst, mains or 12v (3A) operation. excellent selectivity SSB 2 4kHz (1-7,SF) or FM 12kHz. Front panel adjustable VOX and mic gain, a calibrator (1 MHz 10), IkHz readout and linearity, sensitive squelch, clarifier with INT and I RT with ITT (makes FSK easy). switchable "S- and centre zero tuning meter, noise blanker, serviceable plug in boards all contained in 113" (14-) 5r. 11r. 22Ib rigid package 600kHz and 1 6MHz-shifts over 4M Hz. o FT221R £357: VAT VC221 £72.50 VAT M ANUAL £9.50 (No VAT) 10 FT221R 111

THE FT7 MOBILE FL110 ALL BAND LINEAR AMP This is a 10-80m. transceiver VFO controlled (to 1 kHz accuracy) plus TRANSCEIVER crystal control facility Selectable srdebands. CW. crystal calibrator, 10•160m Swit- clarifier and an advanced noise blanker are some of the features packed ched L.P.F into a cabinet only a few inches high, but through careful design the front 15W--.200W PIP panel remains remarkably uncluttered. Designed for a linear 10W. Output A l / A 3 1 . consuming only a few Amps it eliminates: 30A cables from the passenger 4W-.75W. FI compartment and the cooling problems& a massive heat sink. Need more Negative feed • power? Flick In a P L110 (a 2001AI PIP linear) installed in any suitable back with ALC to place in you car. exciter. RF sans. ing (Adjustable FT7 Transceiver £300 -i- VAT F1110 Linear £114.60. VAT hang time) writ, ovende THE FT101E THE MOST POPULAR RIG IN THE WORLD The FT101E a complete mains or 12v DC station contained in a compact 30Ib package, 260W Pl P. of SSB (with in-built RF speech processor) 180W, CW and 80W of AM 10 to 160m (incl) 10MHz RX). The sensitive and selective (permeability tuned RF stages and eight-pole crystal filter, receiver offers: threshold adjustable noise blanker. swrIchable 25 and 100kHz calibrator. 5k clarifier (with separate on/Of switch), etc. etc The VFO us stable and linear (readout to IkHz) external VFO or crystal control can be selected with LED indicators illuminated accordingly. Carrier level is adjustable for, tune up. AM and for CW operation. whose performance with the semi break in keying, with side tone, and the optional filter installed in a high order, Linear and transverier provisions are made with sockets for relay contacts. ALC output, an internal HT supplies. low level RF heater links and switches. etc. etc FT1 01 E FT1 01 E £485.. VAT FTTOTEE £469 + VAT FT101EX £440+ VAT THE FT901 -SIMPLY UNBELIEVABLE PERFOR MANCE

160 10m (n WWV Rs) 12 and 234v (PSU Built•In) SSB, AM, CW. FSK and FM (TX & RX). 180W. PIP, 80W Fl. Analogue IkHz and Digital to 100Hz. Sensitive.ipV with AGC controlled Mosfet RF to push pull F67 NF, Balance active mixer, push pull IF amp, to crystal filter then noise blanker. Continuously variable selectivity 300Flz to 2 4kHz and fixed 600Hz. 2.4kHz, 6kHz and 12kHz (at 6dB) 80dB cross mod 'electron. 90dB desensitisation immunity (at 20kHz off at 14MHz) Audio Peak and separate notch tuning Negative RF feedback an 61468 toroidal tuned output stage (-31dB 3rd order) RF processor VOX Curtis electronic keyer tune button (10sec on full power) PIA. VFO with memory for any TX RX or T/RX frequency Modular plug-in construchon permability tuning (for possible new band allocations) 25kHz calibrator 20dB switchable attenuaior sidetone clarifier, advance noise blanker are all features of the F1901 -- 7 he 1980's Transceiver available FT901D M £805 VAT FT901D £695 i VAT FT9010E £695.00 + VAT

STOP PRESS 160m to 70cms. SSB•C W-A M-FSK• FM CO-CHANNEL. SPLIT. REPEATER. SATELLITE. SCANNING. ETC. The best amateur transceiver now has the best range of accessories. The YC901, AT U/ Power meter. the SP901(P) speaker (patch) The Y0901 monitor scope. the FV901 external VFO-not just an oscillator but digital and analogue readout, multi channel memory with manual and auto scanning The FTV901transvener: another first, a three-band transverter (with repeater shift) 50 (70). 144 and 432MHz (8MHz) in a standard external speaker size box. Watch this space for further details as soon as they become available. E & E.O.

S. M.C. (Jack Tweedy) LTD NORTHER N (LEE DS) BR A N CH S.M.C. (Jack Tweedy) LTD Roger Baines. G3YBO Colin Tho mas G3PS M Jock Tweedy. G3ZY 79 Chatsworth Rd. 257 Otley Road, Ham Shack. Roughton Lane, Chesterfield. Derbyshire Leeds 16. Yorkshire Woodhall Spa Lincolnshire AL.14 k. Chesterfield (0246) 34982 Tel: Leeds (0532) 782326 Woodhal I Spa (0526) 52793 9.5 Tues -Sat 9 -5: Mon Wed & Fri Sat 9-5 Tues -Sat ( • appt)

RADIO COM MUNICATION June 1978 463 SOUTH MIDLANDS COMMUNICATIONS LTD. OSB OR NE RO A D, TOTTON Cables: Aerial Southampton Telex: 477351 SMCO M M G SOUTH A MPTON SO4 4DN Tel: Totton (04216) 7333 Leeds, Chesterfield, VVoodhall Spa. Agents GM, GW, GI etc.

SIVIC YOUR SINGLE STOP SOURCE FOR ALL YOUR NEEDS THE NAG 144XL LINEAR The NAG 144XL-2200 is the finest 2m. Linear Amplifier of its type we have yet seen. Identical in size ,r.--eil M.111111111111r, to the FT-221, it produces about 250W R MS of clean stable putout from a grounded grid 4CX 350F for a nominal IOW drive. The mains PSU using a large cut-core power transformer is built in and .44 provides e 12V 3 amp fully protected and stabilised output for 12V only exciters. A switchable. 10d8 gain, low noise Mosfet receiver amplifier (filtered by a large three section helical filter), a large coax change over relay. RF sensing (with adjustable delay) and manual control, an excellent directional coupler (for the inbuilt SWIR bridge), thermal delay on switch on (anode current CM = meter illuminated red for first 60 seconds), a thermal cut out situated in the valve exhaust stream (optional timer available to leave blower on for 90 seconds after switch off), a grid current sensing ALC output socket, are but a few of the star features IMPORTED DIRECT FROM THE FACTORY FOR THE UK [365 VAT. FREE SECURICOR DELIVERY

SCANNING DIGITAL II from KYOKUTO The Digital II offers complete 551-1z step coverage across Iwo metres and now with the Scanner 40. 25kHz channels from 145M Hz upwards covered in around 10 seconds. It offers full lock and lockout on all channels. The scanner stops ono required channel for 7 seconds, then unless locked moves on. The bright digital readout comes from six seven-segment LEDs. Selectable 10or 1W output for simplex or duplex (up and down shifts), across 144-146 (RX to 149MHz) from a tiny 61- 2" x 7r. Easily undardash mounted with the supplied mounting bracket, or slipped in place of the broadcast wireless. DIGITAL II £235 SCANNER £49.50 (+VAT 14%) For strong handling, and low noise the RF mixer, first IF (16.9MHz) second mixer (and LO) are all FET's. The front end is tuned by varicaps by the DC output of the PLI with superb selectivity provided by a 15-pole ( * 8kHz at -6c18 *15kHz at -70dB). Ceramic filter. LED lamps indicate if the PLL in unlocked or the squelch open. The VCO is directly modulated (for exceedingly linear deviation). Unitary 6 circuit block construction (lot serviceability and screening) Selective calling socket. SMC MONITOR SCOPE The SMC monnorscope allows 'on the air' monitoring SWEEP SPEED: 20-200Hz of a transmitter envelope between 500kHz and 30M Hz RF POWER CAPABILITY: 10-2000 watts PEP. MAX. E.H.T. ON C.R. TUBE: 1500V. D.C. quo. - handling powers up to 2kW PEP (1kW average). This . , TONE OSCILLATORS: Nominally 1.3kliz and 2.3kHz. permits the T.X. to be -talked up- to full power whilst TONE LEVEL OUTPUT: 0.50mV rms per Tone at checking for distortion and -splatter- caused by "flat 50Kohm, t topping". A two-lone audio test generator is in- POWER REQUIREMENT: 115/230V. 45-65Hz. corporated for SSB transmittei/lineai linearity and A.C. *20% 10 watts. INPUT/OUTPUT IMPEDANCE: 50-75 ohms $0239 power output adjustment. Amplitude modulation and PANEL CONTROLS: Intensity/Power on/off Switch: morse keying characteristics can be observed on this focus: vertical gain: honzontal shift; horizontal gain: most competitively priced unit. audio tone (single or 2.tone); tone level; sweep speed EX-STOCK £69 ( 8%VAT) p&p f1 50 REAR CONTROLS: Assn), tone balance, "Y" shift. The 2015 transceives across 144-146 (RX to 149) MHz in 5kHz steps tuned by KYOKUTO DENSHI coaxial switch stopped at 0 and 9. A major feature is the four-channel RAM memory (with an internal Ni Cad back up) SCAN NIN G FM2015R which may be programmed direct from the front panel by simply dialling in a frequency, no screw drivers. rto soldering irons, no fuss. Frequencies can be recalled from the memory instantly or they may be scanned in either of two modes:-searching lot a vacant or an occupied channel, five split (including s and - 600kHz) for repealer or tiansvenor (even triplevertor) use. Multipurpose tone burst, RIT (centre off with -click"), modular constructions, centre zero meter, accessory socket, mounting bracket, microphone etc., are all provided. The sensitive receiver is varicap tuned by the DC level of the PLLIFs of 16-9M Hz and 455kHz provide high image rejection and good shape factor 2:1 at 10dB (12kHz BW). In the transmitter, modulation is applied directly to the VCO (for the ultimate in fidelity), auto power control and vaticap tuning keeps power output constant at band edges and spurii way down Ex-STOCK. f 245 + VAT (12;%). H A N D HEL D TR A N S CEIVE R VHF/UHF MONITOR RECEIVERS SEIVVA MR2, MS2 & MR3 ( VAT prices) KEN KP202 ( +VAT Price) Ideal for the pocket monitor applications, pro- 144MHz. FM. 2W of RF and PAr of audio. fessional SWL, repeater monitor, raynet, net, YL Immunity to breakthrough etc. Tiny (2;" x lr x4," M*2) (2k" er 4r Performance to rival all walkie-taikies and many a MR3) and light. 8oz. Slips into pocket or onto your mobile set. belt with optional case Sensitive double con-. C/w F plug, leather handle/whip case and teles- version superhet with 12kHz band-width, auto copic whip. squelch and generous audio output, comes with Fitted six channels 520 and S21 plus choice Nicads, mains charger, ear piece, antenna etc. from S (21. 23. 24. 0) R (3, 4. 5, 6, 7) .. . , £114.50 MR2G 145MHz 12 switched channels £62.00 R channel only crystii toile burst .. £10.00 MR2A11A 130MHz Aircrah band '2G £64.00 Flexible stubby antenna .. £5.95 MR2(4) 70MHz 12 switched channels £70.00 £4 95 MS2 145MHz 4 scanning channels £75.00 F to UHF adaptor f1 65 MR3V 145MHz 2 switched channels £8500 Nicads . £9.00 M R3U 432MHz Single channel £99.00 Base charger KCP2 £12.75 Case MR2 or MR3 £1.90 CrystiThs stock. £2.20

464 RADIO COM MUNICATION June 1978 Ltd

presents presents a new addition to the famous C Line from R. L. Drake Co the "Crême de la Crême" of Radio Communications

DRAKE TR-7 solid state continuous coverage synthesized hf system is a transceiver and when the DR-7 Digital Readout option is installed it is also a general coverage receiver to 30MHz and a 150M Hz frequency counter It has features previously unheard of that could only have been conceived by the most brilliant designers who are active radio hams We could go on all night about it The Drake TR-7 significantly advances the technology of world-wide radio communications and unfolds an entirely new state of the art for details send 15p stamps or 4 international reply coupons ACCESS DRAKE * SALES * SERVICE BARCLAYCARD BARCLAYCARD 188 BROADHURST GARDENS, RADIO SHACK IT D• LONDON NVV6 3AY Giro Account No. 588 7151 Telephone: 01-624 7174 Cables: Radio Shack, NWfi. Telex: 23718 •

RADIO COM MUNICATION June 1978 465 t h WATERS & STANTON TELEPHONE HOCKLEY (03 704) (1835 (2 LINES)

FDK MU LT I -800D

* 25 Watts FM * Automatic tuning * Non-volatile memory * New mic up/down freq control

A MAZIN G £249 inc VAT VALUE 5) You won't have to retune the front-panel frequency selector for reverse repeater working or monitoring the input frequency--the hick of a front-panel control is all that is necessary. 6) The memory 'snot lost when you switch off the ignition or unplug the rig—it's The Multi-800D is the latest 2m transceiver to leave the production line in Japan. It there always and it can memorise two frequencies not just one I is a fully synthesised transceiver covering 144-148MHz with a full bodied 25 watts 7) It doesn't rust have one repeater shift— you can programme any shift you wish plus output to give you longer distance contacts. But Its big attraction is the things in addition to the 600kHz—e.g 1.6MHz for 70cms. it doesn't have. Ironical but ttue I 8) No wrist •aching tuning either—tuning is manual or electronic—you can take a 1) No restricted coverage—you can operate any channel you choose—no need leisurely stroll at 10kHz per second or race across the board at 500kHz per to get the soldering iron out to change the diode matrix. second. 2) No power control on the rear panel: its on the front—and the power is 9) And there are two safety features—every 100kHz of electronic tuning a bleep infinitely variable between 1 and 25 watts—ideal for transverting. sounds- this means less looking at the dial and more eyes on the road—and 3) No tone-burst control on the rear panel—it's automatic but can be defeated by there's also a remote "head-up" display available that enables you to place the a front panel switch. frequency read-out in a position near the line of vision. 4) No confusing channel numbers or doubt whether you have selected the Having read about the things the 800D hasn't got. an SAE will bring you a four-page correct repeater shift—the bright LED read out gives true frequency display on brochure about all the things it has got But flurry--we already have a backlog ol both TX and R X even when working normal or reverse 600kHz repeater shifts orders far the next shipment.

FDK Multi-2700 Mk II FDK QUARTZ-16

mir rivin-rnie

LAST SHIP MENT STILL AT AT OLD PRICE! £489 inc VAT OLD PRICE! £ 1 4 9. 7 5 /nAcT (HP AVAILABLE) (Limited period) \i

There are two types of all-mode 2-metre rigs on the market—the budget ug with its no nonsense bare essentials and the deluxe rig with its many extras If over you needed an excuse to purchase a 2-metre rig for the car here d is. that make operating that much more pleasurable Without doubts the Mufti' We've managed to negotiate a special deal with our factory in Japan The 2700 falls into the latter classification but at a price that is remarkably low result? , t149's worth of engineering that even amazes the most critical compared with its competdors—in fact it is true to say that if we charged you purchaser for its sheer value and performance II you still need convincing then for all the extras the price would be prohibitive. If you want the full story on the thumb through some of the past couple of years advertising to see when a 2- Multi-2700 simply send a 79 stamp for the 4-page brochure But here listed metre FM rig could be bought for less than £1501 The latest factory fresh are just a few of its features: 144-146MHz (143-149MHz on Receive) 16 shipment has just arrived so here's your chance to make the biggest saving ol watts output. vox, IRT. APC. speech compressor. dual VFO control. VCO, 1978f And here's a prediction too - many of you will look back al this synthesized channel switching or analogue vfo, high/low power. advertisement in a few months' trme and be glad you purchased your rig at FM/SSB/CW/AM/ noise blanket. variable AGC, pre•amp. OSCAR receiver such an incredibly low price—just a few will regret they hesitated and found converter, 230 volts AC/12 volts DC. LED readout. RF gain control, separate the price had risen! FM/SSI3 microphone gains. ALC. variable compression. antrvox. variable So what do you get for f149-757-12 watts FM. 25 channel capability (SO. delay, 100fiHz calibrator, squelch, plus or minus 500kHz repeater shift. S20, R3, R4. R5, R6. R7 fitted) 2 priority channels, true S and R channel 1.6MHz repeater shift, microphone, cables. English manual and even a log- readout, channels fitted indicator light. Automatic protection circuit, mic- book I rophone, quick release mobile mount. DC power lead, hardware etc. a 12 In the past 12 months the Yen has risen by no less than 23% against Sterling months' guarantee and tree delivery. (Channels S21,22/23 available at £7.50 extra inc. VAT) and yet the price of the Multi-2700 still remains at £489. Buy nowt

466 RADIO COM MUNICATION June 1978 ELECTRONICS mArSIIDER SERVICE FDK TELEX 897406 • DenTron RADIO (USA) . . . SUPERIOR DESIGN & QUALITY

DenTron DenTron MLA 2500 W2 - _,J 160- 10m 2kVV PEP W ATT METER/ r„..1 •-.---'-ii et" . £695 inc. VAT PEP METER • & delivery IN STOCK NO W! LESS THAN ONE CUBIC FOOT'

* I kW DC continuous * R F. Wattmeter * ALC circuit * Size w x 14- . 14 - * 3 speed cooling * Weight 47Ib * Forward and reflected power * Remote sensing head * Military specifications * Ideal for SSTViRTTY * 160-10 meters * 0 200/0-2000 watts * 234v/117v AC * 3rd order down 30dB i * Also reads PEP * £69- 95 me VAT * 2 of El MAC 8875 tubes * 40 watts drive for lkW

. . . AND HERE'S JUST TWO OF OUR TUNERS 300 W•-3k W! DenTron MT 2000A .- 3kVV.. DenTron .. ONLY £175 Al «en. JR MONITOR inc VAT Deel-L.M ,.• reneelullunel I 160 10m

* Continuous Tuning 1.8 to * Transmatch Circuit: Tune - ,e.'zi. • - 1 3 0 0 W II 30MHz £59 inc. VAT * Front panel grounding out matt reactance. trans- RP form load impedance to & delivery switch for your antenna 50.75 ohms • IN STOCK NO W! system * Built-in heavy duty 4 to 1 * Front Panel bypass balun, 3 cores switching * Harmonic attenuation * Continuous 1 8 30mHz * 75.600ohm balanced * Antenna inputs. Coax un- * Ceramic rotary switch 18 * Forward reading RF indicator * Random wire balanced. SO 239 Ran • position. 12 amp capacity * Built . in Whin * Ceramic 1.000 volt capacitors don) Wi re, ceramic geed_ * Capacitor Spacing 6000 * ideal lot FT101 etc * Mobile mount tbru Balanced line. two Volt * 50 or 75 unbalanced * Ideal lot HE mobiles , ceramic feedthrus. tuned * Low profile styling 5rx feeders 75-660 ohms 14" x 14" * Handles a full 3kW PEP * Weight 16 lbs

OTHER DenTron PRODUCTS MT3000A, £275: 160-10 m Doublet, £22: 'I kW ATU £99.50

-,-,--,e-- ..--:. FD K FD K , err_lrei-7i - ...11 TM 56B 70cms _ M ULTI-Ull é•• VHF M ONITOR i.

The TM56 isone of our most popular models, combining great performance with * Fitted 6 repeaters and 4 ... modest price. The TM568 has the basic receiver design of our mobiles and simplex includes its own 230 volt AC Supply, plus external 12v DC input. 12 lined * Automatic tone-burst channel positions are included. plus 4 autoscan positions. Any one of the * 12 watts output Autoscan channels can be cancelled. Price includes 10 channels. R3. R4, R5. * Receiver RF pre-amp R6, R7. SO, S20, S21. S22 and S23. necessary leads etc, and 12 month * Receiver IRT control Fitted 6 repeaters • 4 simplex £259 guarantee Ai f95 it is unbeatable' I 0 channel marine versron £113 Inc VAT * 4 channel autoscan Fitted choice of 2 channels £225

RETAIL MAIL ORDER & HEAD OFFICE: HOCKLEY AUDIO. 31 SPA ROAD. HOCKLEY. ESSEX. TEL. 03 704 6835 I2 lines) , ALL PRICES INCLUDE VAT CARRIAGE CHARGES IN BRACKETS BARCLAYCARD ' Access 0300E Bredhurst Electronics, The Street, Thakenham, Nr Pulborough W. Sussex. Tel 07983•30b6

VISA AGENTS —G3XTX J.R Electronics, 196 Collier Row Lane, Romford. Essex. Tel Romford (0708) 68956 taigiffar_o GM3GRX Eric Simpson. 6 Drossle Road, Falkirk. Stelingshire Tel 0324 24428 ll k MONDAY TO SATURDAY SA M TO 530 P M EARLY CLOSING WEDNESDAY

RADIO COMMUNICArioN June 1978 467 WATERS Et STANTON ELECTRONICS FAST DELIVERY THROUGHOUT UK

PRICE LIST Mosely 1105 SWL Amateur band dipole MBM48/20em elemem Multrbeam yagi 69h £27.00 (1.00) with trombone mounting £21.66 1ST JUNE, 1978 Hygain 12AVO Vertical 2kw 10-15- 20m MI3M48/70cm element Multibeam £39.95 ((2.00) yagi with trombone mounting Hygain 14AVO Vertical 2kw 10-40m £21.662(£2.00) £56.20 (C2.00) MB M88/70cm 88 element Mul- Hygain 18AVT Vertical 2kw 10-80m trbeam yagi with trombone YAESU COM MUNICATIONS £81.45 ((2.00) mounting .. . £28.97 ((2,00) EQUIP MENT (JAPAN) HO-1 -Mini beam- 10-20M £94.00 (C2.00) 8XY/70cm Crossed 8 element yagi com- FRG7 Gen coverage receiver 5.30mHz C4 ''Nlini •vertical" 10•20m £41.50 (£2.00) plete with phasing harness and 'N• AC/DC .. .. £184.50 EL4OX Compact 80/40 dipole inc. balun type connector .. £24.13 ((2.00) FRG7D As above but digital readout 79ft tkw . £29.00 (£1.00) 12XY/70cm Crossed 12 element yagi £227.25 ASP VHF/UHF MOBILE ANTENNAS (USA) complete with phasing harness and FR1010 160-2m+ broadcast ru AC/DC 201; wave standard 2m . . £2.95 (C1.00) 'NI' type connector .. £29.70 ((2.00) £523.00 677 5/8th wave deluxe 2m £14.95 ((1.00) PMH2/70cm 2 way phasing harness for Friel E transceiver 160-10m AC/DC 2009 5/8th wave budget 2m . £7.95 (C1.00) two 70cm yagis .. £5.90 (£1.00) £545.60 667 70cms collinear deluxe £17.71 (£1.00) PMH4/70cm 4 way phasing harness far FT101EE As above less processor 462 70cms budget 3d13 gain antenna four 70cm yams .. £12.26 ((1.00) £527.60 £6.75 (£1.00) 23cm ANTENNA FT101E Extra- narrow CW filter £23.35 'No-hole" Boot mount for all above 015/1296 Double 15 slot-fed yam with FV1018 External vfo for FT101 £82.65 £3.50 (£1.00) type connector .. £22.78 ((1.00) SP10113 External speaker for FT FR K220 Magnetic mount (677/667)+4m COE/STOLLE JAYBEA M ROTATORS Series . £18.56 cable .. . £8.50 (C1.00) (USA/GER MAN/JAPAN) FT200 Transceiver 80-113m 260 watts K220A Magnetic mount AR40 VHF & light HF beams £53.43 £343.00 (2009/467/201) 1-4m cable £8.50 ((1.00) CD44 HF beams .. £106.87 FP200 Matching AC PSU tor above JAYBEA M VHF/UHF ANTENNAS (UK) STOLLE 2010 VHF rotator £48.95 £73.70 4METRE ANTENNAS STOLLE 2030 VHF rotator deluxe con- Y0101 Monitor scope . £166.86 4Y/4M 4 element folded dipole vagi with trol box ,. £54.00 FT221R 2m all mode transceiver AC/DC 11" boom . £12.65 ((2 00). STOLLE Alignment bearing RZ100 £401.60 PMH2/4M 2 way phasing harness for £11.25 YC221 Matching digital readout two 4m yagis . £9.39 ((1.00) 9502 Channel master,. Ideal VHF arrays £81.55 2 METRE ANTENNAS (3 core cable) .. £45:00 (£1.50) FT227R 400 channel FM transceiver 12V C5/2M 5c1E1 glass fibre collinear KR400 1 ton deluxe rotator HF beams (6 DC .. . £214.85 omnidirectional £30.93 (C 2.00) core cable) £95.00 ((1.50) YP150 150 watt dummy load £54.60 5Y/2M 5 element folded dipole yagi with 9523 Alignment bearing for 9502 £9.55 (£1,00) F T9010 Digital 160-10m transceiver 1" boom £7.70 (C 1.25) SWR METERS (JAPAN) 200W _ £781.85 8Y/2M 8 element folded dipole yagi with Single Meter SWR 3mHz-150mHz FT901DM Digital 160-10m transceiver 1" boom . £10.00 (C 1.25) £9.50 200W . £905.00. 10Y/2M 10 element folded dipole 'long Dual Meter SWR/Power 3mHz-150mHz FI? 80-10m transceiver .. £343.00 yagi with 11" boom and trombone £11.95 (0.50) 01R24 Amateur Radio World clock support . £21.32 (£. 1.75) NAIGAI (JAPAN) £15.93 PBM10/2M 10 element Pambeam with 2200 500W PEP 230v linear (10w Drive) YH55 Communication headphones 11" boom and trombone support £399.00 ((4.50) £9.85 boom . £25.36 (£ 2.00) S A.E colour brochure. YD844 Desk microphone £20.25 PBM14/2M 14 element "Parabeam with MICRO WAVE MODULES (UK) YD846 Hand microphone . £8.40 II- boom and 45' braces £31.16 (£ 2.00) MMT 432/28S Transverter £133.88 (n C.) FT225R Details t.b.a . £528.75. 5XY/2M Crossed 5 element yagi wit h h11" MMT432/144R Transverter £169.88 (n.c.) FT225RD Details t.b.a £569.12 boom .. . £15.98 (£ 1.5 0) MMT144/28 Transvenet £88.88 (n.c.) FRG7000 Details t Oa. . £320.60 8%Y/2M Crossed 8 element yagi wit h11" MMC144/2.4 4-6: 28-30 cony DENTRON RADIO COMPANY HF boom . . .. £19.91 ((1.75) £20.25 (n.c.) EQUIP MENT (USA) 10XY/2M Crossed 10 element yagi with MMC144/28L0 Convener £22.50 (n.c.) MLA2500 160-10m Military quality am- 1." boo:it £26.32 ((2.00) M MC70/28 28.7 cony. . £20.25 (n.c.) plifier 2KW pep continuous PMH/12C 2 way phasing harness for MMC70/28 LO Converter £22.50 (n.c.) £695.00 (n c.) circular polarisation .. £5.06 ((1.00) MMC432/144 or 28 convener £27.00 (no.) MT3000A 160-10m ATU-SWR/PEP- 5 04/2M 4 element quad yagi £16.31 ((1.50) MMC1296/144 or 28 converter way selector 3KW . £275 (n c.) 06/2M 6 element quad yagi £21.71 (£2.00) £31.50 (n.c.) MT2000A 160-10m ATt./ . long wire. D5/2M Double 5 slot-fed yaw with 1 " MMD050 50mHz counter £66.96 (n.c.) coax, balanced feed 3KW £175.00 (n.c.) booms £13.61 ((1.50) MM D050/500 500mHz counter 160.10AT 160-10m ATU long wire, 08/2M Double 8 slot-fed yagi with 1" £85.32 (no.) coax, balanced feed 1KW £99.50 (n.c.) booms . . £18.22. (£2.00) MM D500P 500mHz pre-scaler £27.00 (n.c.) MONITOR 160-10m ATU as above. Rt SVMK/2M Mounting kit for vertical po• MMV1296 70 23cm triplet £33.75 (n.c.) indicator. 300 watts.. £59.95 (me) larisation tor 2 slot-fed vagis £3.82 ((1.00) MMP 12/3 transverter PSU £56.25 (n.c.) W-2 160-10m SWR/PO WER METER 2 METRE ANTENNAS (Cont'd) SHURE MICROPHONES (USA) 0•200/02KW DC/PEP £89.95 (n c.) UGP/2M Unipole and ground plane 444 50k base station £25.50 ((1.00) 160-10m Doublet Tuned feeders £7.03 (£1.00) 5261 500-50Kbase station £32.50 (£1.00) £26.00 (n c.) H0/2M Mobile 'Halo' head only £3.26 (0.75) 201 50K hand•held £11.25 (£1.00) DTR•1 HF transceiver-new 1978 model HM/2M Mobile 'Halo' with 24- mast INTERFERENCE ACCESSORIES t.b.e. £3.88 ((1.00) HP3A UHF TV High pass filter £2.95 (0.25) A separate catalogue on Dentron is available PMH2/2M 2 way phasing harness for TV33 OOLP Low pass filter 2KW priced 25p. refundable. two 2m aerials .. £6.80 (£1 00 £18.00 (0.75) HF ANTENNAS (UK & USA) PMH4/2M 4 way phasing harness for Ferrite rings 11' dram .. 0.30 (0.05). Mosely TA33 (high power) 10-15.20m four 2m aerials £16.33 (C1.00) KATSU MI K EVERS 3 el . . £119.25 (2.50) 70cm Antennas EK121 Electronic Keyer (6v DC) Mosely TA33 JR 400W PEP 10.15-20m CB/70cm 8db glass fibre collinear. 8-45 wpm .. £29.95 (0.75) 3 el. . _ £106.87 (2.50) omnidirectional . . £39.37 ((2.00) ICO M Mosely TA32 JR 400W PEP 10-15.20m 08/70cm Double islot-fed yagi with r IC202 SSE1 hand held portable 3 watts 2e1 £72.00 (2.50) booms .. .. £15.46 ((1.50) £162.00 Mosely TD3JR Wire dipole 10-15. PBM18/70cm 18 element Parabearn IC240 FM 22 channel transceiver 20m- 2311 . . £24.20 (1.00) yarn with lr boom £18.56 ((r_50) £189.00

BARCLAYCARD M AIL OR DER & HEAD OFFICE: Access -n HOCKLEY AU DIO. 31 SPA ROA D, HO CKLEY. ESSEX. TEL: 03 704 6835 (2 lines) ALL PRICES INCLUDE VAT CARRIAGE CHARGES IN BRACKETS FOR AGENTS SEE PREVIOUS PAGE At\

468 RADIO COMMUNICATION June 1978 Opposite South Harrow Tube and Bus Stations NEC awe Bale AMCO M M SERVICES

194A Northolt Road YAE SU FDK South Harrow, Middx W eie London. Tel: 01-864 1166 \-1

YAESU MUSEN FRG-7 Now available with FM Detector at £172.50 Inc' YAESU PRICE LIST (FREE DELIVERY) ROTATORS VAT FT101E . £453-00 FT301D £585.00 (inc. Carr. plus VAT) FT101EE £438-00 F1301SD £465.00 Also for FRG7-FM FT301 . £490.00 F1101 EX • £413.00 Ar20 Light VHF/UHF £34.00 Detector Module-Simple fitting- FL2100B • £279.00 FT301S £355.00 Full instructions included FP301D £135.00 AR3OLight VHF/UHF £41 00 FV1018 £69.00 AR22VHF Light HF £43.00 £11.50 incl. VAT and postage SP101B FP301 . • £85.00 • £16.50 AR4OVHF Light HF £47.50 FRG7 Analogue SP101PB £37.50 FV301 . £70.50 AR33 Deluxe control '40 £172.00 mcl VAT and Delivery .Y0100 £139.00 SP120 £15.50 FT227R FL110.. £110-50 £59.00 FT200 . £285-00 811 Medium duty £79.50 £189.00 incl. VAT and Carriage F P200 . • 'YO301 £145.00 £6o•oo CI44 Medium duty £95.00 FV200.. • £67.00 LL301 . . £26-00 HAM II Heavy duty £129.00 Fil 301 Relay box £9.00 JUST TELEPHONE YOUR CARD NUMBER OR £279.00 2010/220 Automatic £43.50 FRG7 £15400 FC301 £86.00 SEND YOUR CHEOUE WITH ORDER 2030 Memomatic £48.00 FR101 D.Dig. £505.00 F19010 £647.00 BEARINGS £435.00 F1901 DE £647.00 FR101D . CD562 CDE (up to r and FR101 S. Dig. £435.00 FT901SD £632.00 FR101S £349.00 FT901 DM • £749-00 RZ100 Stone (balbace) FL101 'YCSOOE • • £265.00 £359.00 £10 00 FL101RF £393.00 'YC500S £21000 FT227R £179.00 •VC500..1 £145-50 FT221R £349.00 'YP150 £46-50 01-864 1166 01-422 9585 FT223 ("Itch.) £139.50 • These items VAT 8%. others ICO M FTV250 £149.00 12}% C215. 2m. 8ch . £132-50 MICRO WAVE MODULES PRICES SUBJECT TO CHANGE WITHOUT NOTICE C215. 2m. 1 Och. .. £142.00 MMC70 4m Converter £20.25 C202. 2m. SSS . £152.90 MMC144/28 LO 2m Converter £22.50 C22A. 10W Mobile £145.00 MMC32/28 70cm Converter .. £27.00 C240. 10W. Mobile £164-40 M MC1296/28 23cm Converter £31.50 SST T-2 ULTRA TUNER C245E. 10W. FM/SSB MMC1296/144 23cM Converter £31.50 £352.00 MMV1296 23cm Tripler . . . £33.75 C211E. 10W. FM/SSB MMD050 50 MHz Counter . £66.96 Plus 14% VAT £470.00 MM0500P Prescaler . £27.00 M MD500P 500 MHz Counter ... £85.32 MMT432/28 70cm Transverter £133.88 MMT432/144 70cm Transverter £169.88 MMT 144/28 2m Transvertei £88.87 FDK JAYBEA M OM ANTENNAS Multi U1 70cni mobile £221 4Y/4M 4 el. yagi £12.65 ([2-00) Multi 11.2m mobile £184 PMH 2/4M 2 way harness £8.35 (75p) Multi 2700 Fm/ssb Tx/un £435 2M ANTENNAS +14% VAT C5/2M 5 dB collinear £30.95 (£2 00) 5Y/2M 5 el yaw £7.70 (f 1 00) Tunes OUI SWR on any coax fed antenna as well as random wires. S MC 8Y/2M 8 el yagi £10.00 (Cl 00) Works great on all bands (160-10 metres) with any transceiver 10Y/2M 10 el. yagi £21.32 (f 1 50) running up to 200 watts power output. M ONITOR PBM 10/2M parabeam £26.37 (f 1 50) Increases usable band width of any antenna. Tunes out SWR on PVM 14/2M parabeam £31-16 (f2-00) SCOPE £69+ 8% mobile whips from Inside your car. Ideal for receivers. 5XY/2M 5 el. x'd yagi £15.97 (£1 50) DELIVERY FREE. 8XY/2M Sel x'd yagi . £19 ,91 (£2 00) Uses toroid inductor and specially made capacitors for small size: 10%Y/2M 8 el. x-cl yagi £26.25 (£2 00) 5.1" x 21' x 2-1". Rugged. yet compact. Attractive bronze finished PMEI/2C Circular harness £6.00 (50p) enclosure. SO-239 coax connectors are used for transmitter input * * 04/2M 4 el quad .. £16.31 (£1 50) and coax fed antennas. Convenient binding posts are provided for 06/2M 6 el. quad . £21.71 (£2 00) random wire and ground connections. FO R VISITORS TO O5/2M el. slot .. £13.61 (£1 50) ONLY £32.50 inc. VAT and carriage O8/2M el. slot .. £18.22 ([1 50) LONDON SVMK/2M vertical slot it £3.83 (£1 00) PLACE YOUR ORDER BY UGP/2M ground Plane £7.03 (Cl 00) 0 M70 Post +Tax paid everywhere PHONE H0/2M halo head .. £3.26 (75p) 70/28 MHz Converter £18-50 WE'LL DELIVER TO YOUR HM/2M halo + mast . £3.88 (75p) 144/28MHz Converter .. £16-5O HOTEL OR MEET YOU ON PMH2/2M 2-way harness moo (75p) 432/28MHz Convener £22-00 DEPARTURE. AND PHH4/2M 4-way harness £16.34 (Cl 00) 432/144 MHz Convener £22.00 ACCO MPANY YOU TO 70cm. ANTENNAS 432 4 434/28 MHz Converter .. £26.00 THE LANDING OFFICER D8/70cm 8e1. slot .. £15.47 (Cl 50) 432+434/144 MHz Converter .. £26.00 TO ARRANGE CARRIAGE PBM 18/70cm. Parabeam £18.56 ([1-50) 28/70 MHz 2 Watt Solid State Transverter . £52-00 OF YOUR PURCHASE. MBM48/70cm Multibeam £21.65 (£2 00) 28/144 MHz 2 Watt Solid State Transverter £52-00 MBM88/70cm Multibeam £28.97 (£2 00) BUCCANEER 28/144 MHz 15 Watt Solid State Transverter £79.00 * * * 12XY/70cm 12 el. s'd yagi £29-70 (£2 00) SCORPION High Power 28/144 MHz Transverter . £93-00 POWER SUPPLIES PMH2/70cm harness. £5.00 (50p) 40/50 Watt 144 MHz Linear Amplifier £45.00 SWR BRIDGES. PMH4/70crn. harness .. £12.26 (£1 00) COUGAR 144/432 MHz FM Transverter £55.00 ETC.. ETC.. ETC. C8/70cm. 8dB colines; £39.07 (£2 00) COBRA 144/432 MHz FM Transvener E73.50

SECURICOR - HIRE PU R C H ASE - ALL EQ UIP ME N TS SER VICE D

RADIO COMMUNICATION June 1978 469 PAUL G3VJF ICO M FOR QUALITY

SIMPLY THE BEST! available ex-stock and delivery is free. IC-202 4111C-202 IC-215 1C202 The 2m SSB/CW ponable which is clean £169 inc. VAT enough to use as a prime mover to drive a linear The £159 inc. VAT VXO gives continuous coverage over the ranges and delivery 144.2 and 144.2-144-4. The coverage can be extended with ostra crystals swrIc hable from the front paneL This is the ideal set to buy if you are thinking of sampling the delights and advantages of SSS on 2m as it gives full coverage of the SSS and CW portions of the band with easy. continuous tuning. Now available ex stock, delivered free for £169 inc VAT.

IC-215 I> IC-215 By far the best 2m FM portable on the market— with more power (3W) than most and batteries some 4 times as big thus giving a reasonable period of operating use. Add to this the superb, clear modulation for which ICOM are so famous and a good receiver, plus a solid, reliable construction and you have really good value for money Total channel capacity =15 Channels fitted 9(S20, S22, R3, R4, R5, R6, R7, R(1. R91

Now available ex•siock at £159 inc VAT and delivery.

I Li 'I 00.01. MCA. .000 I I C r _t 4 IC-240 IC.24(1 Think of the features you would instal in a mobile to provide a s u pE R-8 CA N combination ol optimum usefulness AND SAFETY. You will probably come up with the following requirements: 1 Easy channel selection with minimum knob twiddling—yet with all the normal FM channels available. 2 A fully automatic tone burst which operates only in repeat mode with NO buttons to press either on the front or on the back of the set. 3 Instant reverse repeat at the thck of a switch without any re-tuning or It memory programming. 4 A very sensitive receiver with a spurious response performance far 2.311 better than the average and a very clean transmitter with excellent clear, crisp modulation. (We measured a sensitivity of 01 Iry pd for 10dB „ sinad). 5 A reasonable price—but (more important) a quick, reliable after sales service COMPARE THIS LIST WITH PREVIOUS ADS FOR VARIOUS TRANSCEIVERS AND YOU WILL SEE THAT THE 240 WINS EVERY TIME: IC-240 alone £198 inc. VAT SUPER SCAN £77.63 inc. VAT Fitting £6.00 extra IC • 240 with superscan £275

WE NO W STOCK THE J-BEA M RANGE OF ANTENNAS AT HERNE BAY

AGENTS (PH O NE FIRST —All evenings only except Norfolk and Burnley) London —Terry G8BA M (01-556 9366) Scotland —lan G M80 0X (0786 822 212) Norfolk —Ted G3FE W (05088 632) W ales— Tony GW3FKO (0222 702982) Burnley —(0282 34841) Midlands —Tony G8AVH (021 329 2305) North West—Gordon G3LE0 (Knutsford (0565) 4040) SH OP: Thanet Northern. Wo mbwell. Barnsley. S Yorks. (0226) 756229

H.P. TER MS AVAILABLE

FOR ALL MAIL OR DERS AN D SALES DURIN G BUSINESS HOURS

YOUR SOLE AUTH ORISE D UK IMP ORTER FOR ICO M Access THAN ET ELECTRONICS 143 Reculver Road, Beltingo, Herne Bay, Kent (02273 63859)

470 RADIO COMMUNICATION June 1978 DAVE THANET FOR SERVICE G4ELP

WITH THE TECHNICAL KNO WLEDGE AND EQUIP MENT TO SERVICE THE M PROPERLY BOTH BEFORE AND AFTER SALES

IC-211E Y £549 inc VAT Giving you FM/C W/USB/LSB, all produced from the amazing ICOM synthesizer and patent 1St chip. Frequency read out is to the nearest 100Hz and it is amazingly stable and accurate. You can use the two frequency stores as separate VFOs or for any repeater shift required. The tone burst is automatic, of course, and reverse repeat is available at the flick of a switch. Add a keypad (we will give you the circuit to make your own or you will be able to buy one shortly) and find a new facility which is quite impossible with old- fashioned rigs. The original waiting list has now been dealt with 3-1 and you can now have one from stock.

IC-245E £396 inc VAT A

This truly amazing little box gets you 0 9 9 mobile on FM. USE or (if you really think it a good idea) CWI The synthesizer is the same as the IC-211E and can be tuned to the nearest 100Hz, again with amazing accuracy. Of course such a versatile little box will often IC-701 £999 inc VAT 9. be used as a base station and facilities such as keypad operation can be added They are now ex •stock !

The popular "SLIM JIM /I SJ2 144-146 M Hz—High efficiency 2 metre omni-directional vertical An omni-directional 2 metre aerial developed by T & T from a design by F. C. Judd (G2BCX). Derived The HF rig to beat them all. HERE THIS MONTH. * All solid state from the "J" the SJ2 is a free space aerial with including the finals * 100W RF output Continuous Duty on All Bands. All better than 50% greater efficiency than con- Modes * All bands 1.8-30MHz * USE. LSB. CW, CW (narrow), RTTY * ventional ground plane types due to the very low Double balanced Schottky Diode mixer used in both Tx and Rx * Fully angle radiation field The aerial is slim and compact synthesized with Digital readout to 100Hz and two stores to enable split (58 inches long) and as there are no radials it is frequency operation * I CONrs unique bandpass tune *VOX. Semi - break- unobtrusive and has low wind resistance. Supplied in CW. RIT, AGC. Noise Blanker * Built-in RF speech processor * complete with mast clamp. £15.50 inc. VAT Extremely compact * All filters built in *12V or mains operation * Electret (carriage £1.00). desk mic. NO EXTRAS TO BUY_

INTRODUCING A NE W RAN GE OF MICROPH ONES BY LESON. For the time being available only from Herne Bay. All these are suitable for ItOM transceivers and have a PTT switch and a frequency response 300-2500Hz. They are NOT fitted with a plug. M ODEL TYPE BUILT-IN IMPEDANCE AMPLIFIER PRICE TW232 Ceramic Desk mic with PTT, Lock sw and gain cont. fi Silver grey finish Compression amp 0-30dB var. <4-5K £n2c5V0A T)0 DH-218 Moving coil dynamic. Hand held NONE D H-233 Moving coil dynamic. Hand held Pre-amp O-1 5d8 var. < 55000 £9.00£4.99 CH-229 Ceramic noise cancelling. Hand held Compression amp 0-35dB var. 3 5KK £15.00 Post and packing 50p in all cases. Gain controls are external in all cases DURING THE EVENINGS AND AT WEEKENDS WHEN CALLS ARE CHEAP. WHY NOT USE OUR ANSAFONE TO RECOR D YOUR REQUESTS FOR DATA. ETC. (02273) 63850

RA DIO COM MU NICATIO N June 1978 471 Clb ICO M THE FABULOUS IC-701 A LOT OF PO WER AN D A LOT OF ELECTRONICS IN A SMALL CASE

Many who have seen the IC-701 have expressed surprise at its compactness and light weight when compared with its other luxury-rig competitors. This makes it an ideal rig to take out in the car occasionally when the AC psu can be left at home. The complete lack of any 'peaking and tuning and loading controls makes it ideal for mobile use also—and of course this is a boon in the shack as well when you are in a huuy to get that juicy bit of dx The nominal 100 watts of output is available instantly without any clinking of valves while you try to load up in a hurry--and how many rigs with a pair of 6146s in the finals will give this output continuously, even on long sessions of RTTY? Many features and facilities, which are extras with other transceivers, are included in the price, such as: *T WO VFOS * DIGITAL DISPLAY * BOTH AC AND DC POWER SUPPLIES * RTTY FACILITIES * CW FILTER * TRUE RF SPEECH COMPRESSION *A SUPERB ELECTRET DESK MICROPHON E * VOX * S EMI-BREAK IN CW * INTERNAL SPEAKER AS WELL AS ONE IN THE AC PSU. (Thus making it very useful for mobile use.) We have had the demonstration models for some time now and have done exhaustive tests to try to find any possible weaknesses; such as running it into diabolical antenna systems which are as disgraceful. to present to a rig like this, as it would be to try to run a Rolls-Royce on paraffin. We have not managed to blow a PA up yet but of course you don't get much power out under conditions like this and you won't work much as the rig will try to protect itself. The number of reports we have had about the superb quality and punch of the mod are quite incredible—usually given without asking for an opinion! Mind you the electret desk mic is designed to be used as a desk mic, i.e. about a foot away. If you pick it up and bellow into it you can get an 'orrid wooliness which is worse than some rigs sound at their best !The band pass tuning is a treat to use and helps a lot when the "Spaghetti Number One.... " decides to tune up a couple of kHz away with a 40 over 9 signal shouting -Helll0000. ..". Mind you, if he splatters over 10k Hz of the band you cannot make a silk purse out of a sow's ear I Features like this type of variable filtering are extremely useful on today's crowded bands. The sig nal is extremely clean when examined on the spectrum analyser and there is plenty of power to drive a linear. The tuning is a treat to use, with 100Hz readout and 5kHz per revolution of the dial. There is also, of course, a quick tuning facility to get you to the part of the band you want without hours of knob twiddling. The facility to store one frequency in the memory while looking around the band is very useful indeed For instance, you can hold the frequency of a juicy bit of Dx and have a quick look around, even on other bands, while he is finishing his rag-chew. In due course there will be a keypad for remote control, looking a bit like a calculator, with its own frequency display and four memories. After a few months of using the IC-701. and working all over the world with it. we wouldn't be persuaded to change to ANY OTHER HE RIG I They are available from Heme Bay ex- stock at the time of writing and the price is still £999 inc VAT and delivery—but if the Yen gets any stronger you can well guess what's likely to happen! ICO M Simply thE BEst

FROM YOUR UK DISTRIBUTOR THANET ELECTRONICS HERNE BAY KENT

472 RA DIO CO M MU NICATIO N June 1978 William Munro (Invergordon) Limited

distributors for NEC Amateur

Radio

Equipment

01110E DIGITAL READOUT TRANSCEIVER Frequency Range 10M to 160M Modes LS8 use CW AM FSK FAX/SSTV CO 301 LINEAR AMPLIFIER Power Requirements 100/234V AC or 1a5V DC Frequency Range 10M to 160M Input Power 280W PEP (240W on 28M Hz) Mode LS8 USEI CW AM Power Requirements 100/234V AC CO 201 EXTERNAL DIGITAL READOUT VFO Max Input 2KW SSE; 1KW AM Three Outputs 5.0•55MHz 8.2-8 7MHz 8.9-9-4MHz Drive Power 100•200W Frequency Counter 10Hz to 30MHz Circuit 2 x 3-5002 in Grounded Grid Al Output Voltage 2V (p- p) Impedance 50- 100ohms Counter unit input Level 0 IV (p-p) 100kHz M110 DESK MICROPHONE IV (p-p) 100kHz < Dynamic Unidirectional—Impedance 50K—Frequency Range 200-10.000Hz Power Requitements 100/234V AC Flexible Shaft with diecast base for stability and two position Switch.

SP110 EXTERNAL SPEAKER UNIT/DIGITAL CLOCK High Quality Speaker Und 4W 8ohm range 180-8000Hz. Digital Clock with 7-segment display. with 59 minute sleep timer, and 24 hour alarm setting with two AC outlets one unswitched and one switched controlled by clock. Power Fail Indication. Power Requiremenis for Clock 100.234V AC and 50/60Hz switch Selection

* * *

IN ADDITION TO OUR OWN SHO WROO M YOU CAN TEST AND EXA MINE NEC EQUIP MENT AT: NEC AMCOMM SERVICES. 194A Northolt Road. South Harrow, Middlesex Tel 01-864 1166 NEC THANET NORTHERN, 64 High Street. Wombwell, Yorks Tel 0226 756229 TOP Y BLACKMORE, 2 Joseph Parry Close, Llandough, Penanh, S. Glamorgan CF6 1PL Tel 0222 702982 L. A. WILES & SON, Aisthorpe, Scampion. Lincoln Tel 0522 71 351 * * *

WE ALSO STOCK Antennas and accessories--Microwave Modules- Polar Electronic Developments— Modular Communications Systems— Amex Products—Components. Semiconductors etc.

USED EQUIP MENT —Please contact us for up-to-date information on our stock

Telephone 0349 -852351 100 HIGH STREET, INVERGORDON, ROSS-SHIRE V18 ODN Telex 75265

ACCESS BARCLAYCARD HIRE PURCHASE

RADIO COM MUNICATION June 1978 473 LO WE ELEC T R O NICS LTD

TR7500 The sensible one. £225 inc. VAT The TR7500 gives you the ultimate FM mobile ng. Full band coveiage 144-146MHz in 80 channels at 25kHz spacing—and no programnung or crystals due to the use of an advanced synthesiser. Dial indication is commonsense itself; d you want $20. simply turn the dial to 20. R7. turn to 7. no need to remember complicated frequency plans. If you are opeiating on a tepeater and you wish to listen on the input frequency or °petal° reverse repeater, simply touch one switch, there is no knob twiddling involved Should you need a 1.6MHz shill—that's also available on the synthesiser— but remember. YOU may qualify for the WACS Award (worked all cop shops') • • Potent performance in a package not much larger than the TR• 2200 with 12 Watts transmitter eit r t output and better than 0-2 0 sensitivity togethei with the unparalleled Trio quality and attention • 1 0 to detail make the TR7500 the senstbie man's choice TO

ele

fe'r Fug° TS700G f 458 Inc. VAT (also including tho matching VOX-3) Say what you will, the TS700G set the standard ton all other 2 metre all mode transceivers A very high standard which has yet to be surpassed. Full 2 metre coverage. V FO or 22 crystal channels. all mode operation AM. FM, USB. LSB and CVY Mains or battery supply. Noimal and reverse repeater facilities at the turn of a switch Trio exclusive tuning lork access tone geneiator with Sully auto tone burst Best quality signal on the band thanks to TRIO design excellence an low intermod amplilieis. It's simply the best reg that you can buy, and it's backed by the combined reputations of TRIO and Lowe Electronics. 15 Watts output .0.25 microvolt sensitivity, first class strong signal handling receiver. European standard selectivity It you haven't yet handled the TS700G. rush to one of our branches and be

Prepared 10 be impressed. Send ton full details now

(VI-R I C) TR 2200GX £147 (3 ch.) £177 02 ch.) inc. VAT This is the definitive 2 metre FM poitable sig which has won praise from all over the world. Over 2W transmitter output with switched reduction to 400m W for local contacts. High gain receiver with double IF filtering at 10.7MHz and 455kl-lz for razor sharp selectivity. The TR2200GX is supplied with all accessories including the battery charger for the optional Nicad battery pack, the removable telescopic antenna, the carrying case, the shoulder strap. external powei lead, microphone and handbook. Fitted with 12 channels, the price is only £177 inc VAT. If you wish to start out at a lower price we can supply the rig fitted 3 channels for only £147 With all its performance. the 1R 22000X is a must for the portable operator. At the price, it has to be the best around. Just look around at the next rally and see how many operators are carrying them Also available are a mobile mounting bracket at £9.70. a matching 10 Watt amplifier for £45 and a flexible antenna. Send for full details now.

0-1- Ft I Cb TR7010 £189 inc. VAT Work real OX with ease on 2 metre SSB and CW The TR7010 combines a high pet f oimance receiver with a 10 Watt transmitter and provides mobile oi fixed station capability at low COSI Supplied toady to operate from 144 1 -144 34MHz. Me TR7010 covers all CW, SSB and beacon activity 48 channels with 5kHz spacing plus VXO and RIT provide continuous coveiage °negation in any other part of the 2 metre band can be carried out by a simple ciystal change and no re-alignment is required. Single conversion using an IF of 10 7MHz with a fast class crystal filter gives outstanding selectivity Wide range melded AGC and newly developed F ET devices in the RF and mixes stages allow maximum sensitivity to be used with freedom horn oveiload due to adjacent signals The single conversion transmitter using fully balanced mixeisgenerates a beautifully clean signal with cusp audio quality Join the SSS gang and work real DX for £189 Send lor full details now

'r RI Q TR3200 £185 inc. VAT The newest FM handy transceiver horn the ever expanding TRIO range. Superb pert ormance tor the 70cm operator with all the advantages of portability and TRIO reliability. 12 channel capability in the range 432-436MHz with three channels fitted (SU8, 18. 20) Transmitter output switched 2W/400m W and incorporating the exclusive TRIO 1750Hz tuning fork access tone generator (does that mean you can ring for credit 7) High gain 5/8 wave antenna for enhanced perf ormance on tiansmit and receive. Supplied complete with all accessoires as for the TR2200GX and including the all impodant battery charger We have lust received the first shipment of the VB3200 10W amplifier for the TR3200. Rather more complex than the V82200, the V83200 also includes a switchable receive pieamplifiei Price £95 inc VAT Send for details now

474 RADIO COM MUNICATION June 1978 LO WE ELECT R O NICS LTD

(t3,'TRIQ TS520S £525 inc VAT Digital readout/counter DG5. £134 inc VAT The logical development of the TS520, one of the world's most popular transceivers now includes full 6 band coverage 160-10 metres with all the performance, reliability and quality we expect from Trio. An outstanding receiver with high sensitivity (02 uV tor 1 OdB S/N ratio on all bands) together with an equally excellent transmitter make the TS5205 the best value for money rig around As a TS520S owner, you go on the air with a sense of pride and confidence. Thousands of these precision built transceivers are in use all over the world—in amateur shacks. field day sites. in DX and contest winning stations and no other rig offers you the performance, dependability. versatility and value that is built in to every TS520S_ See it soon and send for full details today.

)'T RI O TR8300 £244 Mc VAT For the amateur who demands the best performance and top quality engineering in his UHF mobile rig, the TR8300 has to bathe one. This new 70cm FM transceiver from Trio offers power in excess of 10 Watts. receiver performance of a very high order thanks to the use of advanced semiconductor devices in the RF stages (they look like Aspirins with legs) and styling to match the successful TR7010 and TR7200G. Supplied complete with all accessories and fitted with four channels and provision for up to 22. the TR8300 allows instant use of the ever growing number of 70cm repeater stations all over the country. If you travel abroad, the TR8300 will cover all European operation thanks to its' amazing bandwidth without retuning (RX 431-439-5MHz). Send for full details today

'T RI O TS700S £5130 inc VAT This is the ultimate TS700 with every possible extra Full 2 metre coverage on VFO or 22 crystal controlled channels with digital readout on all modes to 100 Hz using the Trio exclusive easy on the eyes readout rubes. Built-in Vox and break .in CW with keyed sidetone. Low power facility for all modes in case you don't need the full 15-18 Watts normally given by the TS700S. Better than ever receive, performance, particularly in strong signal handling when compared to other equipment, and a built•in switched RF preamplifier Automatic tone burst with repeater and reverse repeater shafts for no fuss use of 2 metre repeaters. The remote VF0700S offers for the first time in a VHF rig the facility of splitting transmit and receive frequencies by any amount and also operation on two different transceive frequencies at the touch of a switch (invaluable for monitoring net frequencies or OSCAR checking). The VFO will also give VFO control of the TR7010 with a small adaptor unit. All in all the TS700S is the best, so see it soon at your neatest stockist; you will not be disappointed.

EP'] RI G T R 7400A £334 inc VAT This 2 metre FM mobile rig has taken America by storm, everyone wants it and inevitably we are now being asked to supply it in this country It certainly has everything going for it- 144-148MHz coverage in 800 5kHz steps wit h PLI, stability and digital frequency readout (but I still think that the TR7500 readout is more sensible in Europe G3PCY). It has all repeater and reverse repeater shihs digitally programmed in together with an amazing array of squelch and tone burst facilities including automatic tone burst, sub audible squelch. CTCS (guess what that is) and provision for touch tone pad inputs. The big feature of course is the output power of 30-35 Watts—yes, t said 30-35 Watts. A sensitive receiver to march the TX performance completes the package of the rock crushing TR7400A. Send for details today.

R I 0 TS820 £723 inc VAT DG-1 £36 inc VAT IN THIS SMALL SPACE, WE CANNOT ADEQUATELY DESCRIBE THE BEST HF TRANS- CEIVER ON THE MARKET SEE APRIL/MAY ISSUE FOR DETAILS OR SIMPLY ASK US FOR A LEAFLET JOIN THOSE IN THE KNO W—USE THE TS820

NOW IN STOCK. THE TL922 MATCHING 2.5kW LINEAR. ALSO IN STOCK. THE ATV» ANTENNA TUNER/POWER METER

SEND 45P IN STA MPS FOR CO MPLETE CATALOGUE AND ANTENNA BOOK.

RADIO COM MUNICATION June 1978 475 LO WE ELECT R O NICS LTD

SRX 30 £158.00 inc VAT

For the keen short wave listener and the radio amateur who needs to tune around frequencies other than the amateur bands, the new SRX-30 is the one. This all new receiver covers the entire range of 500k Hz to 30MHz in 30 bands and caters for AM. USB. LSB and CW reception. Using advanced drift cancelling techniques, the SRX-30 is the receiver for stable, trouble-free listening. Housed in a rugged case measuring only 1 2;- a Si." a 9- deep. the SRX• 30 operates from 12Vdc or 100-240Vac and with its built-in speaker, gives high performance, go-anywhere capability. The SRX•30 brings a new high standard to low cost listening-at £1 5800 including VAT, it hes to be seen and used to beappreciated-ask for f ull details now

to show everything we stock-why not send for our catalogue-lust 45p Inc IT'S IMPOSSIBLE postage. Price inc. Price inc. VAT Carriage BITS AND PIECES VAT Carriage E E TRIO OSCILLOSCOPES E E Hansen SWR25 Twin meter .. 10.80 0.67 CS1570 Dual trace dc to 30MHz' 484.40 3.00 FS301 Through tine watt meter 35 to 30MHz 32.40 0.86 CS1560A Dual trace dc to 15MHz' 324.00 3.00 CS1562 Dual trace dc to 10MHz' 270.00 300 DAIWA ACCESSORIES CL-22 Aerial tuner unit. 1.8-30MHz 13.50 0.66 'The price includes two matching lull bandwidth a 10 probes CSW• 216 ATU with built-in SWR meter. 80m-10m PF8I0 In line power meter. 3 power ranges. 1.8-200MHz. 500 P E.P . . . 103.50 3.00 2 way antenna switch . 64.80 3.00 CL-65 ATU 80- lUm 500W P [P. 200W. CW .. 45.00 3.00 C01303G Station monitor scope (as C013030) AT • 400X Stepped attenuate, • 41.04 0.86 but fitted in Irne.RF monitor and 2 tone oscillator .. 129.80 3.00 SWX•777 De luxe SWR/power meter with 'cross over' C013030 Single trace dc to 5MHz. Ideal small service metering . 55.00 1.06 scope 1013.00 3.00 SW-410 SWR/power meter 144MHz/432MHz 48.60 0.86 DM800 Dip resonance meter 48.60 0.85 SW110 SWR/povver meter 1.8-150MHz 25.92 0.85 CDE ROTATORS FILTERS AR40 (5 core cable required .. 51.75 3.00 Trio LF30A Low pass filter I kW rating. 32MHz cut off CD44 (8 core cable required) 106.87 3.00 90dB stop band . 067 Hem-2 (8 core cable required) 145.12 3.00 Trio BPF2A 2m band pass filler-144-146MHz 50W. rms. 100W P.E.P. . . . • 27.00 0.67 RAK ANTENNAS 0-67 Shinwa 1110 2m band pass filter-144-146MHz . 13.72 A-8XL 80m dipole 4kW rating .. 9.50 0.86 Shinwa 1006 2m low pass filter-146MHz cut off 11.48 0.67 AL-48DXN 80/40m trap dipole Length only 28m Shinwa 1140 28MHz transverter filter-28-30MHz 2kW P E P . 20.00 1.06 band pass .. . 13.72 0.67 Listener Ill SWL antenna Double dipole. 24m overall 20.00 0 86 Shinwa 1005 HF low pass filler-32MHzcut Off 10.80 0.67 Listener I SWLantenna Loaded wire antenna_Only 5m long 8.00 0.66 VHF AMATEUR RECEIVERS HD-26A Extendable dipole. Tunable horn approx NR56 Tunable/crystal 2m FM receiver. 144-146MHz 54.00 0.86 70cm to 4m . 6.75 0.44 ASV1515 VHF FM monitor receiver less crystals. KY-GAIN ANTENNAS -HF beams Mains/battery. Self -contained . 28.50 0.86 TH2Mk3 2 element yagi for 70.15 and 10m. 1kW AMR2176 Scanner with 8 crystals. The best and most rating 117.56 3.00 popular. Mains/battery .. . 106.87. 1.06 TH3Jnr 3 element yogi for 20.15 and 10m. 600W Soma MS2 Scanner less crystals. 4 channel pocket . . . 121.50 3.00 67.50 0.67 TH3Mk3 3 element visor for 20.15 and 10m I kW 167.62 3.00 Seiwa. MR2 Monitor tess crystals 12 channel pocket TH6DXX 6 element total 20 15 and 10m 201.37 3.00' receiver 63.00 0.67 'By BRS Crystals for the above-each . . 2.40 0.15 FlYquad 2 element quad 8.5dB gain on 20 15.10m 182.25 3.00

ACCESSORIES HY-GAIN ANTENNAS-HF verticals Trio HS5 Communications headphones 22.00 0.67 12AVO Trapped vertical self •support for 20.15. 10m 39.93 3.00 Trico Low Impedance padded headsets 4.68 0.67 14AVO/W8 Trapped vertical sell-support for 3.00 Maeden Accessory speakers .. . 2.52 0.28 40.20.15 10m ...... 57.19 Morse keys HK708 . .. 8.10 0.67 laavuw8 Trapped vertical self -support for EK150 Katsumi keyer. 240V ac/12V dc operation. 80.40 20 15 10m 81.45 3.00 Built-in monitor .. 80.75 0.67 * J BEA M -FULL RAN GE IN STO CK EK1024 Electrontc key& with 1024 bit memory 118.12 0.67 * MICR O WAVE MO D ULES -ALL IN STO CK RW151D Kuranishi watt meter/dummy load 0.5.25- 150W •dc• 500 MHz 75.60 0.86 * HBR RTTY SYSTE M IN STOCK [WI Wave meter .. 16.20 1.06 * HILO MAST PU MP-UP MASTS-GREAT DL20 20W dummy load 4.67 0.24 * FOR 2 METRE FM -TRY THE UNIDEN 2030. SA ME Tr* HC2 Ham clock .. 15.50 106 PERFOR M A NCE AS THE TR72006 AN D FITTED 11 Hansen SWR3 Single meter . . 9.50 0.67 CH AN NELS -£145 inc VAT Gace ewes faoi earrai TRIO in Eirrinn fàil ô Donald White, Ballyvourney, Macroorn, Co. Cork. Ballymakeera 70.

HEA D OFFICE: 119 Cavendish Road, Matlock, Derbyshire. Tue -Sat. 9am-5.30pm. Telephone - 0629 2430 or 2817 9am-9pm. Telex 377482. BRAN CHES; Communications House, 20 Wallington Square, Wallington. Surrey. SM6 8RG. Telephone. 01 669 6700-closed Saturday afternoons. 27 Cookridge Street, Leeds, Yorkshire. LE2 3AG. Telephone: 0532 452657 Soho House. 362-364 Soho Road, Handsworth, Birmingham 821 90L. Telephone: 021 554 0708-closed Mondays.

AGENTS: John-G3JYG, 16 Harvard Road, Rinomer, Lewes, Sussex. Telephone: Ringmer 81 2071 (evenings and weekends) Sim G M3SAN, 19 Ellismuir Road, Baillieston, Nr Glasgow. Telephone: 041 771 0364 (evenings and weekends) Alan-G W3YSA. 35 Pen Y Wean. [tail Isaf, Nr Pontypridd, Glamorgan Telephone: Newton Llantwit 3803 (evenings and weekends). FOR FULL CATALOGUE AND ANTENNA BOOK SEND 45p IN STAMPS

476 RADIO COMMUNICATION June 1978 DIODES/ZENERS SOCKETS/BRIDGES TRANSISTORS, LEDS, etc, 1N914 100v 10mA .05 8-pin pets .25 ww .45 2N 2222A NPN 12N2222 Plastic .101 .15 14-pin pcb .25 ww .40 252907A PNP .15 1N4005 600v lA .08 2N3906 PNP (Plastic) .10 1N4007 1000v 1A .15 16-pin pcb .25 ww .40 253904 NPN (Plagie) .10 1N4148 75v 10mA .05 18-pin pcb .25 mext .75 253054 NPN .35 1N753A 6.2v z .25 22-pin pcb .45 ww 1.25 253055 NPN 15A 60v .50 T1P1 25 PNP Darlington .35 1N758A 10v z .25 24-pin pcb .35 ww 1.10 LE D Green. Red. Clear. Yellow .15 1N759A 12v z .25 28-pin pcb .35 ww 1.45 D.L.747 7 seg 511r High corn-anode 1.95 1N4733 5.1v z .25 40-pin pcb .50 ww 1.25 XAN72 7 sag cons-anode (Red) 1.25 MAN71 7 seg (Red) 1.25 1N5243 13v 2 .25 corn-anode Molex pins .01 To-3 Sockets .45 MA N3610 7 seg etwAsinods (Orange) 1.25 1N52448 14v z .25 2 Amp Bridge 100.pry 1.20 MAN UA 7 sag corn-anode (Yellow) 1.25 1N5245B 15v z .25 MAN74A 7 rancor's-cathode (Red) 1.50 25 Amp Bridge 200-pry 1.95 FN0359 7 sag consicathode (Red) 1.25

C MOS - T T L - 4000 .15 7400 .15 7473 .25 74176 1.25 74H72 .45 745133 .40 4001 .15 7401 .15 7474 .3o 74180 .75 74H101 .75 74s14o .55 4002 .20 7402 .20 7475 .35 74181 2.25 74H103 .75 745151 .30 4004 3.95 7403 .20 7476 .40 74182 .95 74H106 .95 745153 .35 4006 .95 7404 .15 7480 .55 74190 1.75 745157 .75 4007 .35 7405 .25 7481 .75 74191 1.05 74 LOO .25 745158 .30 4008 .95 7406 .35 7483 .95 74192 .75 74L02 .25 74S194 1.05 4009 .45 7407 .55 7485 .75 74193 .85 74 LO3 .30 745257(81231 1.05 4010 .45 7408 .25 7486 .25 74194 1.25 74 LO4 .30 4011 .20 7409 .15 7489 1.35 74195 .95 74L10 .30 74 L SOO .25 4012 .20 7410 .10 7490 .55 74196 1.25 74 L20 .35 74L501 .35 4013 .40 7411 .25 7491 .95 74197 1.25 74L30 .45 74L502 .35 4014 .95 7412 .30 7492 .95 74198 2.35 74 L47 1.95 741SO4 .30 4015 .90 7413 .35 7493 .35 74221 1.00 74 L51 .45 741.505 .45 4016 .35 7414 1.10 7494 .75 74367 .85 74L55 .65 74 LSO8 .25 4017 1.10 7416 .25 7495 .60 74 L72 .45 741_509 .35 4018 1.10 7417 .40 7496 .80 75108A .35 74L73 .40 74LS10 .35 4019 .50 7420 .15 74100 1.15 75110 .35 14L74 .45 741.S11 .35 4020 .85 7426 .30 74107 .35 75491 .50 74 L75 .55 74 LS20 .25 4021 1.00 7427 .45 74121 .35 75492 . so 74 L93 .55 74 LS21 .25 4022 .85 7430 .15 741 22 .55 74L123 .85 74 LS22 .25 4023 .25 7432 .30 74123 .55 74 HOO .15 74 LS32 .40 4024 .75 7437 .30 741 25 .45 74H01 .25 74500 .35 74 LS37 .35 4025 .30 7438 .35 74126 .35 74 H04 .20 74S02 .35 741_540 .45 4026 1.95 7440 .25 74132 1.35 74 H05 .20 74503 .30 741.542 1.10 4027 .50 7441 1.15 74141 .90 74H08 .35 74604 .30 74 LS51 .50 4028 .95 7442 .45 74150 .85 74H10 .35 74505 .35 74 LS74 .65 4030 .35 7443 .65 74151 .65 74H11 .35 74508 .35 741_586 .65 4033 1.50 7444 .45 741 53 .75 74H1 5 .45 74510 .35 74 LS90 .95 4034 2.45 7445 .65 74154 .95 74H20 .30 74511 .35 74 LS93 .95 4035 1.25 7446 .95 74156 .95 74H21 .25 74520 .35 74LS107 .85 4040 1.35 7447 .95 741 57 .65 74H22 .40 74540 .20 74 LS123 1,00 4041 .69 7448 .65 74161 .85 74H30 .20 74550 .20 74LS151 .95 4042 .95 7450 .25 74163 .85 74H40 .25 74551 .25 7415153 1.20 4043 .95 74 51 .25 74164 .60 74H50 .25 74564 .20 74 LS157 .85 4044 .95 7453 .20 74165 1.50 74H51 .26 74S74 .35 74LS164 1.90 4046 1.75 7454 .25 74166 1.35 74H52 .15 745112 .60 74 LS367 .75 4049 .45 7460 .40 74175 ,ao 74H53J .25 745114 .65 74 LS368 .75 4050 .45 7470 .45 74H55 .20 74C04 .25 4066 .95 7472 .40 74C151 2.25 4069 .40 4071 .35 MCT2 .95 LINEARS, REGUL ATO RS, etc. 4081 .70 8038 3.95 LM32015 1.65 LM340K 15 1.25 LM723 .50 4082 .45 LN1201 .75 LM320T12 1.65 LM340K 18 1.25 LM725N 2.50 MC14409 14.50 LM301 .45 LM320T15 1.65 LM340K24 .95 LM739 1.50 MC 14419 4.85 LM308 drum) .95 LM324N .95 78L05 .75 LM74119.141 .25 LM309H .65 LM339 .95 181.12 .75 LM747 1.10 LM309K 4340K-50115 7805 (340T5) .95 781.15 .75 LM1307 1.25 9000 SERIES LM310 1.15 LM340T12 1.00 78M05 .75 LM1458 .95 9301 .85 95H03 1.10 LM311D (Alinl) .75 LM373 2.95 LM3900 .50 9309 .35 9601 .45 LM340T15 1.00 9322 .75 9602 .45 LM318 (mini) .95 LM340T18 1.00 LM380 0144 PIN) .95 LM75451 .65 LM320K517905)1.65 LM340T24 .95 LM709 m141,151.25 NE555 .50 MICRO'S, RAMS, LM320K 12 1.65 LM 340K 12 1.65 LM711 .45 NE556 .95 CPU'S, ETC. NE565 .95 745188 3110 NE566 1.75 1702A 4.50 NE 567 1.35 MM5314 3.00 INTEGRATED CIRCUITS UNLIMITED MM5316 3.50 2102-1 1.45 7889 Clairemont Mesa Blvd., San Diego, CA 92111 U.S.A. 2102L-1 1.75 SPECIAL No Minimum TR 1602B 4.50 DISCOUNTS TMS 40444551. 14.50 All prices in U.S. dollars. Please add postage to cover method of Total Order Deduct 8080AD 12.00 shipping. Orders over $100 (U.S.) will be shipped air no charge. 535 599 5% 8713 1.50 Payment should be submitted with order in U.S. dollars. $100 • $300 10% 8723 1.50 5301 • $1000 15% All IC's Prime/Guaranteed. All orders shipped same day received. 8724 2.00 $1000 - Up 20% 8797 1.00 21078.4, A 4.00 2708 11.50 Phone (714) 278-4394 BarclayCard / Access / American Express / BankAmericard / Visa / MasterCharge

RADIO CO M M U NICATIO N June 1978 477 AMATEUR ELECTRONICS UK AEUK Your number one

AS FACTORY APPOINTED DISTRIBUTORS WE OFFER YOU — WIDEST CHOICE, LARGEST STOCKS, PRO MPTEST DEAL AND FAST, SURE SERVICE RIGHT THROUGH. • (.-. .. ._ _er--ze. se-- c:IngrED rys ...... •,- -- - . YOU t CC.. ,CC a • .. .i t-, PP e. - _,.., " • ' ' t _.,--- — •._ •7: 34a, • -• A ,i' ' ",...i...;-•r•--• ..i A

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If 111 F

Hours: 9.30-5.30 Continuous including Saturdays—Early closing Wednesday, 1 p.m.

Easy parking on our 70ft forecourt. See last months issue for directions on how to reach us

SOLE @ S ` m irda MAIN dab,‘ ATLAS ir AGENT `._....7,;, R A DI O IN C.c AGENT ELECTRONICS

478 RADIO COMMUNICATION June 1978 AMATEUR ELECTRONICS UK source for YAESU MUSEN! TWO NE W ACES FRO M YAESU!

Once again the World's most progressive manufacturer of Amateur Radio equipment has come up trumps YE .-i and this month you'll find two new aces in the YAESU winning hand—it's an established fact that more YAESU gear is in use than other makes and this has only been achieved by sheer technical excellence, innovation and style. Even the impressive range shown here is but a part of the full YAESU story and only the catalogue can convey the breadth and depth of the YAESU endeavour—why not take advantage of our offer below and get your own copy?

FT-227R Provides new standards of convenience in 2 metre FM communications. A Phase Lock Loop Synthesiser generates 800 channe sin 51cHz steps A between 144 and 148M Hz using an "optical coupling- system for channel selection instead of a rotary switch that could wear out. A memory circuit allows you to memorize any of these 800 channels with return to the memorized frequency at the flip of a switch The standard repeater shift or any other offset frequency can be utilized. Automatic tone burst and advanced circuitry to protect PA transistors from high SWR or reversed supply polarity. See Catalogue Page 19

FT-7 The all-solid state FT-7 mobile transceiver provides high performance on the 80 through 10 metre bands. The operator may select upper or lower sideband or CW operation and the compact package provides many features engineered for convenience while mobile. A single knob provides all transceiver tuning and the state-of -the-art noise blanker minimizes impulse-type noise such as that found in mobile applications The FT-7 is designed for operation directly from your car's 12 volt battery. Can also be used as a base station with the matching FP-4 AC PSU See Catalogue Page 18

FT-901 DM Unparalleled receiver performance plus advanced transmitter features make the FI -901 DM the ham' s dream come true. The receiver features reiection tuning, dual-filter variable band width tuning and audio peak frequency tuning for maximum rejection of unwanted signals. Transmitter includes built-in Cunis keyer and RF Speech Processor and features a 10 second "TUNE" timer to safeguard your finals. Includes memory for both transmit and receive frequencies. an advanced noise blanker and off -set tuning on both transmit and receive. All modes. USB, LS13, CW, FSK. AM and FM. 160 thru 10. See Catalogue Page 3

FT-225RD this is the very latest of the growing 2 metre range and incorporates digital frequency read-out optional repeater shift, variable power output. D noise blanker. selectable AGC and gives all- mode operation on LSE, USB, CW, FM and AM. The 225RD is, of course, fully portable and can be operated off mains supply or 12v DC and has a host of other line features including provision for an optional memory unit Model 225R analog version also available.

FRG-7 The model FRG-7 is a precision built, high performance Communications receiver designed to cover the bands from 0-5MHz-29.9MHz without gap. E The advanced technology employed in its circuitry includes the famous Wadley Loop System drift cancelling technique. This coupled with a triple conversion super heterodyne system guarantees extremely high sensitivity and exceptional stability. Careful design has rninimised unwanted spurious signals so often encountered in cheaper imitations. Features include RF attenuatot selectable audio filter and automatic noise supression circuit See Catalogue page 13

FRG-7000 New all solid-state digital read-out general coverage receiver. Covers horn 0.25-29.9 MHz AM. SSB. CW. Has unique digital clock feature which incorporates timer which controls rear apron connections to external equipment such as tape recorder etc., etc. This de-luxe receiver has everything for the dedicated SWL and professional user and supplements the famous F AG • 7 which continues in production of course.

SPECIAL VOUCHER OFFER Here's a 10-1 winning offer if you'd like the latest Yaesu catalogue. Just send us 4 • 9p stamps (36p) and well send you Yaesu's latest fully illustrated brochure together without Credit Voucher for C3.60 against your eventual purchase. Acouple of stamps will bring you the latest Alias or Swan leaflets or our current used equipment list

BRANCH: A MATEUR ELECTRONICS, UK—COAS1AL, CLIFTONVILLE, KENT, KEN McINNES, G3FTE, THANET (0843) 291297.9 a.m.-10.30 p.m. BRANCH: A MATEUR ELECTRONICS UK SCOTLAND, 287 MAIN STREET, VVISHA W, LANARKSHIRE, GORDON McCALLU M, GM3UCI. TELEPHONE WISHA W 71382. (EVENINGS CARLUKE 70914) AGENT: W ALES & WEST—ROSS CLARE, GW3N WS, CAER LEON, NEWPORT. (CAERLEON 422232)—ONLY 20 MINUTES OVER THE SEVERN BRIDGE.

508-514 AL U M ROC K RO A D 021-327 1497 BIR MING H A M 8 Telex 337045 6313

RADIO COM MUNICATION June 1978 479 THE WORLD LEADER PRICES FRO M Recent major exchange rete variations mean Yaesu prices are being revised upwards by about 10%. New prices are not to hand as we go to press—so please Wcstern phone/write for up•to-date quotafion. BUT...... OF COURSE NO PRICE INCREASE ON FT221 R

All-mode operation—SSB (USB. LSB). CW, AM. FM. All solid- state reliability with plug-in modules. Rugged 70-watt dissipation. PA transistor for stability and reliability. VHF local oscillator (133-137MHz VCO) in PLL system minimises spurious responses. 12 volt dc or ac mains operation built in. Full 4MHz (144-148) coverage with 600kHz repeater shift and access tone generator.

also Digital readout adaptor for FT221 and FT221R. YC221 Mod. kit needed for FT221 and IV models without 'D" suffix to serial number. Details on request.

We/tern Pi licqA S FT221R £392.63 YC221 £75.38 MOD. KIT £383 FREE Securicor Delivery FREE Carriage on Warranty repairs YOURBUY YAES UFRO M W e d e l n FOR FREE Advice and Assistance SEND 15p IN STA MPS FOR LATEST YAESU MUSEN EQUIP MENT CATALOGUE

JOIN IN ON UHF WITH YO UR FT101 (OR OTHER 28M Hz RIG) AN D THE W eiteffl 70TV 432M Hz TRANSVERTER We have designed and built the 70TV up to a high standard. Not down to a price! Don't buy a 70TV if you're looking for a cheap unit. BUT if you want to hear signals that some others can't ... the 70TV is the answer! * Fully stabilised AC and DC PSU * Full 10W. R.M.S. output * Double conversion to minimise spurious outputs * Noise figure 2.5dB typical * Built-in 28MHz attenuator 30:1 * Built-in relays * Matches Yaesu styling * Withstands infinity mismatch this will be the new pacesetter! * All units aligned on Hewlett-Packard Spectrum Analyser * Can be driven by most 28M Hz Transceivers

Ex-Stock Now —ON LY £178.87 1/frctT. 20% OFF IFFTgrol7F7.1Ó1ITH

480 RADIO COM MUNICATION June 1978 Electionics (UK) ltd REACH FOR THE SKY with INESTOINER

"THE STR O N GER ONE" * Standard types, rated at 75mph with full load quoted * Heavy duty types, rated at 100mph * Models from 25-119ft. All telescope down and tilt over * Models for all soil conditions, with/without concrete * Designed by chartered engineers to British standards * Constructed of high quality special alloy steel * Standard model 40% stronger than similar types

A HEAVY DUTY is well worth a little extra ... compare

Size Head Load at 75mph Price (inc VAT)

3S (58(t) 125 lbs £351.00 3HD (58(1) 250 lbs £415.80 4S (75(t) 35 lbs £420.12 4HD (75(1) 66 lbs £496.80

Head loads are for unguyed towers. Prices are for framed-base models (FBP) and are carriage paid except to Scotland, Devon and Cornwall. Over-water deliveries also extra. HEAVY DUTY is up to 100% STRONGER than STANDARD! WESTERN's PEP WATT METERS PM 2000 and PM2001 FIRST IN THE FIELD OF DIRECT PEP MEASURE MENT

Frequency coverage 3.5 to 30MHz (PM2000) 50 to 150MHz (PM2001) Direct measurement of SSI3 PEP output power RMS power measurement for AM. FM or CW Forward or reflected power readings at the flick of a switch Full-scale ranges 200 to 2000 watts (P M2000) 5 to 200 watts (PM2001) Accurate to within 7% No calibration dials to set Large, clear. easy-to•read meter scales Can be left "in-line at all limes

PRICE OF EITHER MODEL £48.60 (inc. VAT)

• Cash or cheques, ACCESS (Nlastercharge), VISA (Barclaycard), PAYMENT • GIRO TRANSFER (A/c 288 6154) HP and Credit arranged — SEN D SAE FOR CURRENT SECONDHAND/SPECIAL OFFER LISTS

Our Agents Southern: Alan Paxton, G4BIZ, Southampton. Hants InuternElactrenici(UH)ltd (0703) 582182 . Scotland: Alan Cameron, GM306J. Altos (0259) 214653 HEAD OFFICE (All Mail /Enquiries) N. Ireland: Les Lyske. GI3CDF. Newtownards (0247) FAIRFIELD ESTATE 812449 LOUTH, LIN CS, LN11 OJH Opening hours: LOUTH: 9-12: 1-5pm Mon-Fri. By appointment Sat 9-12 Tel. Louth (0507) 4955.'6 LEICESTER: May's Hi -Fi. Churchgate (Tel: 0533-58662) Mon-Sat 9-6pm; closed Thurs.

RADIO COM MUNICATION June 1978 481 CR U WE ncouus LTD

JUST BEFORE YOU GO ...

and buy a separate converter to cover 434-436M Hz to monitor the new OSCAR satellite„ take a look at the latest addition to our product range.

DUAL RANGE 432-434MHz & 434-436MHz CONVERTER TYPE: MMC432/28-S & MMC432/144-S

FEATURES

Extra Range (434-436 MHz) (6 For Satellite Reception Jv Ultra Low-Noise First RF Amplifier 4742 MyerW W MEP Stage

Highly Stable Zener Diode Controlled Crystal Oscillator and Multiplier Stages. e SPECIFICATION

Input frequency ranges: 432-434MHz (low) 101MHz (low range) 1 28-30 R.F. connectors : 50 OHM BNC 434-436MHz (high) Oscillator{ 101-5MHz (high range) .I'MHz IF. D.C. Power 11-138 volts I.F. output frequency 28-30MHz or frequencies 96MHz (low range) 1 144.146 requirements 12.51/ nominal 144-146MHz 96-666MHz (high sango),) MHz I.F. Current consumption 50mA Maximum Typical gain - 30dB Size :110.60.31mm Noise ligure 3dEl Maximum Maximum frequency Weight 260g error at 432MHz i 5KHz

DESCRIPTION This 432MHz converter is intended for use with either a 28-30MHz printed strip-line techniques together with an ultra low-noise first or 144-146MHz receiver to produce a high reliability receive R.F. stage, produce a selective receive converter with an overall capability for satellite or terrestrial communication. system noise figure of less than 3.0dB. The unit has two ranges, 432-434MHz and 434-436M Hz. both The zoner diode controlled crystal oscillator uses high-stability 5th for the sanie I.F. output frequency, which may be selected by means overtone quartz crystals which provides high degree of accuracy and of a toggle switch mounted on one end of the diecast case. The stability for the converter. The output from this oscillator is fed into a second range (high) has been included to allow reception of satellite doubler stage, to produce 202M Hz or 203MHz, which in turn is fed signals normally transmitted above 434MHz. into the final multiplier stage to produce the local oscillator injection Incoming 432-434MHz and 434-436MHz signals are fed to the of 404MHz or 406MHz. first R.F. amplifier, which uses a BFR34a low noise silicon transistor. The converter is housed in a highly durable black diecast case, and This signal is further amplified by a BFY90 transistor, before being all circuitry is constructed on high quality glassfibre printed circuit passed to gate 1 of the 3N204 dual-gate MOSFET mixer. The local board. oscillator signal, 404MHz or 406MHz. is applied to gate 2 of this mixer, to produce the required intermediate frequency The use of PRICE: £26.58. VAT. (£29.90 Inc. VAT).

Any further information on the above products and others from our extensive range may be obtained by contacting our sales department, who will be only too pleased to help. INCIDENTALLY. ALL OF OUR PRODUCTS ARE FULLY GUARANTEED FOR 12 MONTHS. MIC R O WAVE M O D ULES BRO O KFIELD DRIVE, AINTREE, LIVERP OOL L9 7AN, EN GLAN D Telephone: 051-523 4011 Telex 628608 MICR O G

482 RA DIO CO M M U NICATIO N June 1978 COUNCIL President RADIO SOCIETY OF GREAT BRITAIN D. S Evans. PhD, BSc, FIM, G3RPE 35 Doughty Street, London WC1 N 2AE Executive Vice- President Telephone 01 837 8688 J. Bazley, G3H Founded 1913 Member society, International Immediate Past-President Incorporated 1926 Amateur Radio Union Lord Wallace of Coslany

Honorary Treasurer P. F D. Cornish. FCA, G 3COR PATR O N: HRH The Prince Philip, Duke of Edinburgh, KG

Telecom munications Liaison Officer R. F. Stevens, G2BVN The national society representing all UK radio amateurs Ordinary me mbers E. J. Allaway. MB, ChB, MRCS, LRCP, Membership is open to all those with an active interest in radio experimentation and G3FK M communication as a hobby Applications for membership should be made to the general P. Balestrini, TEng(CIE). MITE. G3BPT manager, from whom full details of Society services may also be obtained. T. P. Douglas. MBE. AMIEE. G3BA C. H. Parsons, GW8NP R. F. Stevens. G2BVN GENERAL MAN AGER AND SECRETARY EDITOR G. M. C. Stone, CEng. FIEE, FIERE, G3FZL C. J. Thomas. G3PSM D A. Evans, G3OUF A. W. Hutchinson Zonal members Zone A. 6 O'Brien. G2AMV Zone B. J. Anthony. G3KQF AN N U AL SUBS C RIPTIO N RATES Zone C. D. J. Andrews, G3MXJ Zone D. W. A. Scarr, G2WS, MA. FBIS UK corporate: £B. including VAT Overseas: £8. Zone E. D H Adams, GW3VBP Zone F. W. F. McGonigle, GI3GXP Associates under 18: £3. Students aged 18 to 21: £4.50. Zone G. A. M. Allan. GM3ZBE (Student applications should give the member's age at last renewal date and include evidence of student status)

OAPs with 15 years' me mbershio: £4.50. Affiliated societies: £6.50 REGIONAL REPRESENTATIVES (including Radio Communication): £3.25 (excluding Radio Communication) Region 1— W. M Furness, G3SM M Region 2—R. C Andreang. G4C MT Region 3—H. S Pinchin, G3VPE Region 4—T. Darn, G3FGY Region 5—P. F Chilcott. G4BBA Region 6—F. S. G. Rose, G2DRT CO MPOSITION OF RSGB ZONES Region 7—N. A. Smith. G3HFO Region 8—D. N. T. Williams, G3MDO Zone A: Regions 1, 2 and 18 Region 9—H. W. Leonard, G4UZ Zone B: Regions 3.4 and 5 Region 10—R. G. Barren. GW8HEZ Zone C: Regions 7. 8, 16 and 19 Region 11—P. H. Hudson, GW31E0 Zone D: Regions 6. 9, 17 and 20 Region 12—F. Hall, GM8BZX Region 13—A. B Givens, GM3YOR. Zone E: Regions 10 and 11 Region 14-1. McKechnie. GM8DOX Zone F: Region 15 Region 15—H. J. Campbell, GI8FOK Zone G: Regions 12. 13 and 14 Region 16—(Post vacant) Region 17—L. Hawkyard. G5HD Region 18—(Post vacant) CO MPOSITION OF RSGB REGIONS Region 19—R J. Broadbent. G3AAJ Region 1 Cheshire, Cumbria, Greater Manchester, Isle of Man. Lancashire. Region 20—G. Mather, G3GKA Merseyside. Region 2 All that part of Humberside north of River Humber, North Yorkshire. South Yorkshire, West Yorkshire. Region 3 Hereford and Worcester. Salop. Staffordshire. Warwickshire, West Midlands. HON ORARY OFFICERS Region 4 Derbyshire, all that part of Humberside south of River Humber. Awards managers Leicestershire. Lincolnshire, Nottinghamshire. hf C R Emary, G5GH. Region 5 Bedfordshire, Cambridgeshire, Northamptonshire. vhf- Jack Hum. G5U M Region 6 Berkshire. Buckinghamshire. Oxfordshire. Emergency com munications manager Region 7 Greater London south of River Thames, Surrey including that part of P. Balestrini, G3BPT London north of the Thames administered by Surrey Region 8 Kent. East Sussex, West Sussex. Intruder Watch organizer Region 9 Cornwall, Devon S. A. G. Cook, G5X6 Region 10 Dyfed. Gwent, Mid Glamorgan, Powys. South Glamorgan. West Microwave manager Glamorgan. D. S Evans, G3RPE Region 11 Clwyd. Gwynedd. Slo w morse organizer Region 12 Grampian. Highland, Island Authorities. Tayside. M. A. C MacBrayne. G3KGU Region 13 Borders. Fife, Lothian Taped lecture library curator Region 14 Central, Dumfries and Galloway, Strathclyde. S. W. Coursey, G3JJC Region 15 Northern Ireland. Trophies manager Region 16 Essex, Norfolk. Suffolk. P. A Miles. G3KDB Region 17 Isle of Wight, Channel Islands, Dorset, Hampshire, Wiltshire. Region 18 Cleveland, Durham. Northumberland. Tyne 8. Wear VHF manager: I F White. G3SEK Region 19 Greater London north of River Thames. Hertfordshire Region 20 Avon, Gloucester, Somerset Correspondence to RRs and honorary officers should be addressed directly to them (071-1R)_

RA DIO CO M M U NICATIO N June 1978 483 CURRENT COM MENT

GB2RS The I44MHz transmissions have been discussed in Members may like to know that good progress is being detail, and the committee is likely to recommend made by the committee that has been set up to investigate frequencies and modes that will be receivable on most of the Society's News Bulletin Service. Some 40 letters were the equipment currently in use. received in response to the request for suggestions that As far as the contents are concerned there appears to be appeared in the September 1977 issue of Radio Com- a demand for information about local events. However, munication. Several of the letters represented the views of the members of the committee are concerned lest the groups of members. bulletins should become a repetition of what has already It will be appreciated that any significant changes in the appeared in Radio Communication. service will require amendments to the existing licence Nevertheless it is thought that there is a demand for and that the Home Office, as licensing authority, will have local news. It has been suggested that this could go out on to give its approval. vhf (in addition to the national news) and that the The ad hoc committee will be recommending a change national news only would go out on 3.5MHz. This would in the 3.5MHz band frequency. Most letters asked for at least make the administration reasonably clean cut— this. However, as 3,600kHz is in the rtty allocation especially if the zonal manager and regional repre- supported by the IARU, of which the RSGB is a member, sentatives were brought into the organization of the it is not anticipated that there will be a return to that service. frequency. 3,650kHz is the Belgium society's frequency The opportunity is taken to record grateful thanks to for their news bulletin, so we do not feel able to remain G3KQF who took over the "chair" during the writer's there. However, once a frequency has been established it temporary indisposition, and to G3BA who compiled the is felt that it eventually "punches its own hole" in the first draft report. band. G2AM V

JOTA 21-22 October 1978 There has been confusion about the dates for "Jamboree QTC on the Air" this year. due to 1 October being a Sunday. JOTA is always held on the third full weekend in October, amateur rodio news which this year is 21-22 October. and not 15-16 October as many people had assumed. All requested special event callsigns for this event have Licensing matters been recorded by the Society for these dates, and the Following negotiation between the Home Office and the necessary applications will be made to the Home Office in Society there are three decisions to report: due course. (i) the Home Office will now accept applications for the Phase 3 uhf repeaters and also special experimental projects such as microwave repeaters. Further meetings ZL2MHF will take place concerning vhf repeaters. The New Zealand beacon ZL2MHF situated on Mount (ii) applications can now be accepted for special event Climie is now operating on a frequency of 28.23MHz. stations using the 144MHz band and above. These will In order that propagation on the 28M Hz band can be use the new prefix GB8. All applications for special event investigated, it would be appreciated if signal reports of stations should be made through the Society. the beacon could be forwarded either by the QSL Bureau (iii) stations operating under the amateur (maritime) or direct to: The Secretary, NZART Branch 63, PO Box licence on the hf bands will no longer be restricted to 40212, Upper Hutt, New Zealand. crystal control.

With apologies. . . . Stolen property Dr E. H. Squance, G180JG, apologizes for the following On 29 March, in Leicester: Yaesu FT75 mobile psu, rf error which appeared in his article "Calculation of and volume knobs missing. Information to Sunbase distances between QTHs using scientific calculators" in International. the Hill, Oaks Road, Great Glen, Leices- the May issue. In the execution program, for Step to 17 ter: tel 053539 2202. read Step to 18. Between 26 March and 4 April from M61 motorway, at Bamber Bridge, Preston: (a) two Shibaden cctv cameras, Mr J. T. Evans, G3V DB, author of "A cmos rtty serial numbers 110149 and 140148, each fitted with 75mm modulator fer new tones", also in the May issue, draws Cosmicor lens serial numbers 18168 and 14006 or 16356; attention to the omission of a short piece of track from the (b) vhf base station type CM151, modified for cctv, component side of the pcb diagram on page 318. manufactured by Communicators Ltd; (c) two grey Referring to the component layout on page 319, the plastic distribution boxes, one containing 30V psu. missing track runs between the two circular pads Olin to Information to Detective Inspector Thompson. Lanc- the right of R26 and 0.2in below IC6 pin 8. ashire Constabulary. tel Leyland 33561.

484 RADIO COMMUNICATION June 1978 RSGB NATIONAL MOBILE RALLY SCOTTISH MOBILE RALLY

Woburn Abbey Palace of Art Bellahouston, Glasgow

6 August 1978 Saturday 10 June 1978 11am-6pm Details of trade stands available from Norman Miller, G3MVV, "Avon -. Gardiners Lane. Crays Hill, Billericay, Essex. Trade stands, demonstrations, raffles etc. Visitors wishing to stay overnight with self-contained caravans Snack bar. may do so at £1.65 per night. Because of the wild deer in the Talk-in on GB3S MR SO and S24; also monitoring local vhf park no camping with tents or awnings is permitted. Booking and uhf repeaters. forms available from G3MVV on receipt of sae. Full details from GM4FD M, OTHR.

Now available Radio Amateur Old Timers' Association The twentieth reunion of RAOTA was held on 21 April at 80-meter DXing The Horseshoe, Tottenham Court Road. London WI. An attendance of 31 included Lord and Lady Wallace of by John Devoldere, ON4UN Coslany; Dr Rudi Stuber, HB9T: Mr Ray Ashmore, G8KYY. of Wireless World; and Mrs Yvonne Ashmore. This is a complete manual for the serious 80m dxer by an enthusiast who since 1962 has worked nearly 300 countries on Mr Ashmore took the place of Mr Tom Ivan, the W W the band. Success like this comes only through a sound editor, who was unable to attend. A pleasant evening of understanding of the fundamental principles involved, but as nostalgia was enjoyed by those present. well as explaining these clearly, the author also shares a few secrets that could make all the difference. The next reunion is duc to take place on Friday 27 Chapter titles are: 80m propagation; Antennas tor 80m April. 1979. dxing; The 80m dxer's station; Operating practices for 80m. Any radio amateur who has held a transmitting licence 71 + viii pages (A4 format) £2.86 incl p&p for a consecutive period of 25 years is eligible to join RAOTA. Details of membership can be obtained from Miss May Gadsden, 79 New River Crescent. London N13 5RQ: tel 01-882 1272. The G3PAO Memorial Lecture The Verulam Amateur Radio Club's G3PAO Memorial Lecture was held in the Market Hall, St Albans, on 23 March. This annual event is to Worked All Britain AGM 1978 commemorate George Slaughter. G3PAO, founder member and one- At the annual general meeting of WAB held on 23 April time chairman, secretary and newsletter editor of the VARC. who died 1978. there was considerable discussion on the apparently in 1977. Pat Gowen, G3I0R, chairman of AMSAT UK. gave a talk covering all aspects of satellite operation, past, present and future. misleading statement which appeared in a number of Those members and visitors present. over 80 in all and including publications last year. The statement included in publicity G3PAO's widow and family, enjoyed a first-class lecture. relative to the WAB Counties Award suggested that "all profits are donated to RAIBC". This is not strictly accurate, and the committee would like it known that while a fixed sum per year is, and will continue to be, set aside for RAIBC. for many reasons this is not as suggested "all pro fus".

Please return Will the Welsh swl who took away Eddystone and Hallicrafter receiver handbooks, please return them to Rayer, Longdon Heath. Upton-on-Severn. Worcs. as promised.

1979 NRSA Exhibition The 1979 Northern Radio Societies Association Radio and Electronics Exhibition is to be held at Belle Vue. Manchester, on Sunday 22 April. The organizers of the 1978 exhibition wish to a Some of the personalities who were present (I to r): Ron apologize for the overcrowded conditions at this year's Broadbent. G3AAJ. RR for Region 19 and hon sec of AMSAT event and would ask visitors to note that next year's event UK; Brian Pickford. G4DUS, hon sec of Verulam ARC; Pat Gowen: Derek Purchese, G3LXP. chairman VARC; John will be at the same venue but in a hall some 2! times the Swinnerton, G2YS. past-president of RSG13; and Jim Sleight, size of this year's exhibition area. G30JI, county controller for Hertfordshire Raynet

RADIO COMMUNICATION June 1978 485 The diagram matic representation of Fig 4

Two antiphase signals of the same frequency and equal amplitude will cancel out if added together. This is shown radio signals in the phase diagrams (Fig 3) by vector addition. Two signals of the same frequency, but differing in phase by 90° can also be added by vector addition (Fig 4); the resultant by D. M. CLOKE, G4B M0' here is at a different phase angle from either of the two signals added to produce it. Thus the phase and amplitude of the signal resulting from the addition of two or more signals of the same frequency may be found by their The phase diagra m vector addition. Any radio signal can be expressed in a mathematical form. However, the mathematics are complex, and an easier and more visual way of describing a radio signal is A mplitude modulation by the use of phase diagrams. By using a diagrammatic If a carrier wave is modulated by a single sine-wave tone. method it is possible to understand the theory behind two sidebands of equal amplitude are produced, equally such circuits as the phasing method of producing ssb, spaced in frequency on either side of the carrier. Shown as without the use of any mathematical notation. a phase diagram, the lower sideband will rotate around the base line at a slower speed than the carrier; the upper sideband, having a higher frequency, will rotate faster than the carrier. To simplify the following diagrams, the carrier can be considered to be stationary, the upper and E lower sidebands then appearing to rotate in opposite frequency directions. In the previous diagrams a phase advance has been Fig 1 shown as a clockwise rotation, and the same convention will be used throughout; the upper sidebands in the following diagrams rotating clockwise and the lower sidebands anticlockwise. The resulting phase diagrams of an amplitude modulated carrier are best shown in relation to the modulating No Advanced Advanced Advanced phase-shift by 90' by lee by 27e af, which in Fig 5 is single sine-wave tone. A single sine (or retarded wave af signal will also be used in all subsequent diagrams by 90') except where the text indicates otherwise. (a) ( b ) ( c ) (d) Now consider the same af signal simultaneously Fig 2 modulating two independent rf carriers of the same Fig I represents a single radio carrier wave on an frequency, but one rf signal advanced in phase by 90° (Fig amplitude/frequency diagram, but this diagram is incap- 6). Repeat this procedure with the same two rf signals, but able of distinguishing between the above carrier and the with the af signal advanced in phase by 90° in both cases same carrier at a different phase angle. However, if this (Fig 7). carrier is shown rotating around the base line at such a The phase diagrams in Figs 6 and 7 are the key to the speed that the angle of rotation is the phase angle. then a phasing method of producing ssb. phase advance can be shown as a phase diagram (Figs 2 (a)—(d)). Of course, any carrier wave is always advancing in phase—by 360°/cycle. Thus it can be considered in the a I wave diagram to be continuously rotating around the base line. As the frequency of the carrier is increased, the speed of rotation will also increase. time

+ us lb Fig 3 'carrier 1st. )7' Resultant phase diagrams of the am signal

'The Homestead. Smithy Lane. Mouldsu unit Chester CH3 8AR Fig 6

486 RADIO COMMUNICATION June 1978 At peak a f cycle

No phase-shift rf signal advanced 90' Output of balanced Output of balanced s Sb output Fig 6 modulator (1) modulator (2) using (upper sideband (dotted line indicates a 90" advanced al in this case) suppressed carrier) signal and 90* retarded signal

Fig 9

interest, for though at first sight it appears to relax the Both rf and at requirements for this method, the same basic problem of al advanced 90* advanced 90' making accurate wideband af phase shift networks still Fig 7 remains; indeed the smaller the angle used, the more accurate the phase shifts have to be.

SSB —The phasing method Fig 8 shows a block diagram of a phasing type exciter. Applying phase diagrams to the outputs of the two balanced modulators it is possible to demonstrate how the ssb is produced (Fig 9). As two signals of equal Output of balanced Output of balanced ssb output amplitude and opposite phase cancel out, the lower modulator (1) modulator (2) (lower sideband sideband in Fig 9 is suppressed and the upper sidebands using a 45* advanced in this case) reinforce each other to give the upper sideband ssb at signal and 135' advanced rf signal output. Phase diagrams will also reveal that a 90° phase shift is Fig 10 not a fundamental requirement of this method; any angle of phase shift can be used for either the af or rf signals, as long as both angles are the same, and one signal is also SSB —The third method phase inverted by 180°. Thus the af shift could be 45°, and The problem of making accurate wideband phase shift the rf phase shift either 135° (ie 180-45) or 225° (ie networks is overcome in a third method exciter in an 180 +45). However, the output falls as the phase angle interesting way that also has its own set of problems. The moves further from 90°, such that, using a 45° af phase "third method" can be considered as a phasing exciter shift, the final ssb output will be 3dB less than using a 90° with several modifications designed to produce a 90° shift af shift. A 0° or 180° shift will give zero output. To see how in the af signal without a wideband phase shift network. angles other than 90° can produce ssb in this circuit, phase However, the signals produced 90° out of phase, though diagrams are again applied to the phasing type exciter; in the af spectrum, are actually the lower sidebands of a this time using a 45° advanced af phase shift and a 135° filter method ssb exciter working at very low frequency. advanced rf signal (Fig 10). To see how the third method works, phase diagrams will The output is lower than using two 90° phase shifts and again be applied to each stage of the circuit. is also shifted in phase. Phase shift is, however, un- Fig Il shows the block diagram of a third method important in a single sideband signal. The use of angles exciter. The If oscillator normally has a frequency of other than 90° in a phasing exciter is largely of theoretical about 1•6kHz, ie in the middle of the audio frequency spectrum. However, the theory is easier to understand if the If oscillator is above the af spectrum at a frequency of Balanced about 4kHz, and this case will be considered first. modulator (1) Double Balanced balanced Lowil-tepassr modulator modulator (1) ( 3 )

Ilk ssb a f ii r I ssb l ale" ampl If ler oscillator oscillator 90"shift 90"shift gestalt ikestiltt

Double \ I Balanced Balanced balanced Low-pass modulator modulator modulator I liter (2) (2) (4)

Fig 8 Fig 11

RADIO COM MUNICATION June 1978 487 Output of double After low-pass filter Output of balanced balanced modulator (1) modulator (3)

lower e sideband O frequency Audio 1.9 Fig 12 spectrum MHz input 4 kH

Output of double After low-pass filter Output of balanced balanced modulator (2) modulator (4) with t osc advanced 90' rf ont advanced oc

The lowpass filter has a cut off at the same frequency as Suppressed rf signal the If signal. For the purpose of the diagrams an rf 1 Wanted ! Unwanted oscillator frequency of I .9MHz will be used as an sideband I signal example. ib Applying phase diagrams to a third method exciter, E using an If oscillator frequency of 4kHz, and an audio le spectrum instead of a single frequency sine wave af signal, 1.896 1.9 1.904 MHz frequency gives the set of diagrams in Fig 12. It is important to note that the two signals, 90° out of phase, which are fed into Fig 14 the second pair of balanced modulators, are not audio signals but the lower sidebands of the first mixing process. bandwidth occurs. This unwanted signal is, however, not Another point which arises is that the filters can be either the lower sideband in the case of an upper sideband lowpass or highpass, with the same cut-off frequency. exciter the suppression of this unwanted sideband being Using highpass filters in Fig 12 would mean that the wholly determined by the lowpass filter. balanced modulators (1) and (2) need only be single To see how the third method works with an If oscillator balanced; the af appearing in their outputs being removed frequency in the middle of the af range, phase diagrams by the filters. are again applied to the block diagram of the third method exciter (Fig I 1). First, an af frequency below the If Suppressed oscillator frequency will be considered, and for the sake of rf signal simplicity a single sine-wave tone is used throughout (Fig

Unwanted Wanted I 16). signal sideband I To show what happens to af frequencies above the If oscillator frequency of 1-6kHz, a problem arises, as the modulating signal is higher in frequency than the signal being modulated, and so the lower sideband of such a 1.896 1.9 MHz frequency process will be a negative frequency. To overcome this difficulty, in the following diagrams the If signal is Fig 13 considered to be modulating the af. This does not affect the final result, but it does simplify the diagrams. Applying phase diagrams to the third method exciter with The heart of a third method exciter is the lowpass (or an af frequency higher than the If signal gives Fig 17. highpass) filter, which must be good enough to suppress the unwanted sideband. To show the effect of removing the filters, the resulting spectrum is shown on an Receiver bf o amplitude/frequency graph in Fig 13. The effect of tune here —4 inaccuracy in any phase shift is likewise shown in Fig 14. Figs 13 and 14 clearly show the difference in the output spectrum with the two specified "fault" conditions. A ib 2 3 4 third method exciter using an If oscillator frequency of E 5 4kHz might have inadequate lowpass filters, some error in one of the phase shift networks, and some af leak frequency through the first balance modulators, producing an 1 Wanted sideband output spectrum as in Fig 15. S ideband due to inadequate low-pass filters However, in practice an If oscillator frequency of about 3 Sidebands due to a leak Into second balanced modulators 1.6kHz is normally used. This leads to the advantage that 4 Signal due to inaccurate phase shifts 5 Signal due to inaccurate phase shifts and poor low-pass in the event of an error in any phase shift angle, the filters unwanted sideband of the second mixing process appears in the background of the wanted signal and no increase in Fig 15

488 RADIO COMMUNICATION June 1978 (2) The modulators fed with the If carrier and the af signal must be double balanced to stop any af appearing in their outputs. This is not a requirement if Output of double After low-pass Output of balanced highpass filters and an If oscillator frequency of about balanced Idler modulator (3) t 1.30 modulator (I) 4kHz or over are used. Thus, any output from the lower exciter that occurs without the If oscillator running is sIdeband duc to af leaking through the double-balanced modulators and is a fault condition as such (provided that stopping the If oscillator does not unbalance the Output al double Alter loe-pass Output of balanced balanced titer modulator 14 modulators). modulator 12) re osc advanced 90' w 1th If °se advanced 90' Suppressed Fig 18 rf oscillator , Wanted signal e The result is interesting. By comparing Figs 16 and 17 it will be seen that when using an If oscillator at a frequency Unwanted signal É due to gross in the middle of the audio spectrum, that part of the af error in phase- signal above the low frequency appears above the rf signal frequency shift angles frequency, while the af below the If signal frequency appears below the rf signal (this can be reversed by Fig 19 exchanging the inputs to either balanced modulator). (3) There should be tailoring of the af spectrum to ensure that the overall bandwidth is kept to a minimum. Suppressed I at signai — I (4) Frequencies lower than about 1•6kHz cannot be used for the If oscillator signal as the lower sideband of the first mixing process becomes inverted about the After low-pass. Output of double SS 0Hz point and will then appear on top of the upper •I sine balanced Idler vrave nput modulator (I) sideband. In this condition the filter could not separate sldne;rno out the wanted sideband.

Frequency modulation and phase Output Of double Alter lovepass Output of balenced modulation balanced filter modulator (4) modulator (2) Theoretically, an fm transmission has an infinite band- with If osc advanced 90' width because theory tells us that the number of Fig 17 sidebands produced in any fm transmission are infinite in number. However, in practice only the first few sidebands The effect of any imbalance of the balanced modulators are at a significant level (although there are people on working at rf will cause a I -6kHz tone to appear on the 144MHz who attempt to verify the theory!) Indeed, in transmission when correctly tuned on a receiver. Imbal- true nbfm only the first pair of sidebands are significant. ance of the double balanced modulators suppressing the If signal will result in carrier leak on the received transmission. These two "fault" conditions are illustrated in Fig 18. The effect of a gross error in any of the phase shift angles when using a I.6kHz If signal is shown in Fig 19. It is interesting to compare the output spectra of Figs 19 and 14 where the If signal frequencies are 1.6 and 4k Hz respectively. This clearly shows the advantage of the 1•6kHz frequency when any phase angle error is present. Fig 20 In summary, the following points must apply to any third method ssb exciter: The spectral distribution of narrow-band fm is shown (1) The low (or high) pass filters must be good enough in Fig 20 as a phase diagram. The sideband distribution to suppress the unwanted sideband. No simple filter shown reveals some interesting points: can produce a 60dB cut-off within 300Hz at 1•6kHz. ( I) It resembles the spectrum of an a.m. signal, with the major difference that the lower sideband is 180° out of phase with its a.m. counterpart. 1.-- Signal due to I 1 oscillator (2) The bandwidth of an nbfm signal is only slightly dl leakthrough' causes greater than the equivalent a.m. signal. The minimum carrier leak on received J signal possible bandwidth for an fm system is the same as that 2.— Signal due to rf oscillator required for a.m., as reducing the deviation level to a E 'leakthrough' causes li very low amount only decreases the amplitude of the 1.6kHz tone on received significant sidebands. frequency signal As the deviation level is increased in an fm transmitter, Fig 18 the output spectrum changes in a way quite unlike an a.m.

RADIO COMMUNICATION June 1978 489 The interesting relationships between a.m., fm and pm (phase modulation) are best demonstrated by considering Carrier the same af signal to be fed into a modulator of each modulation method (Fig 23). This shows the important difference between fm and pm—they produce the same output spectra, but out of phase with each other by 90°. This means that fm and pm can only be separated by reference to the original modulating signal. The phase diagrams also show that it is possible to produce nbfm by Fig 21 phase shifting one sideband of an a.m. signal by 180° (or signal—this is better shown in two dimensions (Fig 21). phase modulation by phase shifting both sidebands. or The carrier is reduced in amplitude, and the higher order the carrier, by 90°). This is the so-called "indirect fm" sidebands become significant. At certain deviation levels system, and can be used in practice with the type of circuit the carrier will have zero amplitude. To determine the given in block form in Fig 24. amplitude of any component of an fm signal. Bessel Comparing the phase diagrams of a.m., fm and pm in functions give a useful set of graphs (Fig 22). Fig 23 suggests several interesting possibilities when the diagrams are added together. These mixed-mode 0 additions will now be considered. Carrier I B 1st s deband a f Balanced Foe _ Addition l 6 • amplifier modulator e 2nd sideband 10-0- Phase I 4 modulation output

;c:b. l 2 E a Carnee I.._ 90* o oscillator[ shift et

Invertedo Fig 24 phase 0 0 1 2 3 4 5 6 7 e 9 10 Modulation index - Fig 22 Mixed mode modulation The addition of the a.m. and fm spectral components due However, in the following phase diagrams a low to the same modulating signal would result in cancel- deviation level is assumed, and only the first pair of lation of the first lower sideband of the fm signal, leaving sidebands are considered. It must therefore be re- an ssb full carrier signal. However, this presents a membered that the following phase diagrams do not show practical difficulty, as the carrier must be phase coherent the higher order sidebands—which for nbfm is a good (je from the same source) in any addition of this kind, and approximation. once a carrier is frequency modulated the fm sidebands will appear on all outputs. Any later a.m. will also

Single-tone sine-wave af signal modulate those sidebands, causing sidebands of sidebands to appear! Nevertheless, if an fm signal is also subsequently modulated by the same af signal, the lower sideband is cancelled when the amplitude of fm and a.m. is adjusted correctly. This is only an approximate ssb (full time carrier) signal, as only the first lower sideband of the fm signal can be completely cancelled. To find the spectral content of such a signal. phase diagrams can be applied to each fm sideband in turn to produce all the resulting a.m. sidebands—the resulting sidebands can then by added by am vector addition to produce the overall final spectrum. Such a method of cancelling a sideband cannot produce ))* an overall sideband suppression of suitable quality for serious transmission, due to the presence of higher order sidebands and intermodulation of the a.m. and fm fm sidebands. However, the block diagram of such an exciter (Fig 25) reveals that any unwanted fm of an a.m.

Approx s s b t (full carrier) output. when amplitudes of pm Carrier oscillator Arn e tude am 81m correct at and 10-0— amplifier modulator )7v,» I m modulator Fig 23 Fig 25

490 RADIO COMMUNICATION June 1978 modulators, an approximate ssb (full carrier) signal will Phase be produced. By also phase shifting one of the rf signals by modulator 180° the carrier can also be cancelled, giving an ssb suppressed carrier signal. Such a circuit is shown in block form in Fig 26. Applying phase diagrams to such an ssb 90 .shif t i. exciter demonstrates how the ssb is formed (Fig 27). Approximate ssb Again it must be stressed that the ssb produced by any a f Carrier (suppressed method involving fm or pm can only produce an amplifie oscillator carrier) output approximate ssb spectrum, even when very low deviation levels are used. Indeed, the output from such an exciter 180'shif t may better be described as an asymmetrical signal, rather Ir than ssb. As noted previously, the spectrum of a phase modu- Amplitude lated signal that has been subsequently amplitude modulator modulated with the same audio signal will be symmetri- cal. The signal produced in such a process is not without Fig 26 interest, as many a.m. transmitters undoubtedly have transmitter will show up as an asymmetry of the some unwanted phase modulation taking place as well. transmission. Such a signal will have a complex spectral output due to Referring back to Fig 23 shows that the addition of the formation of"sidebands of sidebands"; however, the a.m. and pm signals. modulated by the same af, will not resultant signal will have the characteristics of both a.m. result in the cancellation of any sideband. However, if a and pm and will be resolvable to some degree on both 90° phase shift is used in the audio feed to one of the types of receiving detector. This gives a useful way of detecting unwanted pm on an a.m. transmission.

Ackno wledge ment The author would like to thank Mr C. M. Parry. G8J FJ, for his help in preparing this article.

References

Output of phase Output of amplitude ssb (lower side- [I] D. H. O. Bebbington, G8GGB: personal modulator with modulator with band) suppressed communication. 9e advanced al lee advancecl r carrier [2] "Modulation, Noise, & Spectral Analysis", P. F. Fig 27 Panter. McGraw-Hill, New York.

NEW PRODUCTS

Antenna tuners MFJ Enterprises announce a range of three new tuners using air-wound coils. Top of the line is the MFJ-941 Versa Tuner 2 featuring The MFJ Versa Tuner 2 a built-in swr bridge, dual-range wattmeter (30 and 300W) and a six-way antenna selection switch. Designed for use between 3 and 30MHz, the maximum power capability is 300W. The MFJ-901 is a tuner unit handling up to 200W and covering the same frequency range. The Buzz plug MFJ-900 Econo Tuner is similar to the MFJ-901 Versa A I 3A plug with a built-in alarm is now available from Tuner except that it does not have the 1:4 balun for Wellco Electric Ltd. The buzz plug sounds when the feeding balanced lines found in the two more expensive power fails or a fuse blows. The plug contains a 1.5V tuners. SO-239 connectors are provided for transmitter battery (size N) and requires no special wiring. It is input and coaxial fed antennas. USA prices for the three suitable for the many applications where continuous units are $79.95, $59.95 and $49.95 respectively. power has to be maintained. The suggested retail price is Further information can be obtained from MFJ £5.69 incl VAT. The buzz plug is obtainable from Wellco Enterprises, PO Box 494. Mississippi State, MS 39762, Electric Ltd. Wilbury Way. Hitchin. Herts. SG4 OTZ; USA. tel 0462 52651

RADIO COM MUNICATION June 1978 491 figures. The signal-input end of the guide can be of any A simple lOGHz convenient length. and it is fitted with a matching screw or screws to match the mixer diode to the waveguide. The length of the waveguide at the local oscillator end is receiver with critical: it needs to be made electrically an odd number of quarter guide wavelengths. ie n4/4, where n is I, 3. 5. 7 etc as is convenient. This rear cavity is closed by the same iris as is used to define the Gunn oscillator cavity. transmitter option A basic problem in the design of receivers is how to couple the local oscillator drive into the mixer while by D. EVANS, G3RPE, and C. SUCKLING, keeping to a minimum the amount of signal lost by its coupling with the local oscillator circuitry. A feature of G3VVDG• the present design is that this isolation is provided simply by using the iris to undercouple the Gunn oscillator. Apart from simplifying construction compared with Introduction other methods of achieving isolation, for example by During recent years amateurs have had much success with using a directional coUpler, the present method has the simple lOGHz equipment. Usually this has consisted of important advantage of enabling the loaded Q of the transmitters generating a mere I-20mW, receivers using Gunn oscillator to be significantly increased. This means point-contact diode mixers and with an i.f. bandwidth of that the stability of the Gunn oscillator is improved. 100-200k-11z, and horn or dish antennas having gains of which in turn raises the overall efficiency of the receiver. 20-35dB. Provided that the equipment is operated to take advantage of low-loss propagation modes, such as that Practical details over line-of-sight paths or of super-refraction via ducts, Two forms of the mixer assembly (which were developed then contacts over paths hundreds of kilometres long can quite independently) are shown in Figs 2(a) and 2(b). Also be achieved virtually as a matter of routine. shown as Fig 2(c) is a recommended design of Gunn Both calculations and direct measurements show that oscillator which is the G8APP design [I] with a fixed this size of equipment usually has a reserve of system gain rather than adjustable rf short. A feature of the design of tens of decibels. This reserve means that it is not even given in Fig 2(a) is that it requires the minimum amount necessary for the equipment to be working well for it to be of tools in its fabrication. Points that can be made with successful: an overall efficiency of one per cent may be all respect to its construction are: that is required to cope with most low-loss paths. It also (a) First drill a hole about 3/32in diameter centrally means that "compromise" techniques, such as the use of a through the broad faces of a suitable length of waveguide Gunn oscillator as a self-oscillating mixer (and usually 16 and open one of the holes to 0.25in diameter. also as the transmitter), are quite satisfactory under these (b) Remove the brass centre boss from a knob intended propagation conditions provided that the rest of the to be used with a 0.25in diameter shaft by breaking away system is working reasonably well. the surrounding bakelite. Fit the two flanges in their However, for paths containing obstructions the path positions and solder these and the boss in a single losses are normally very much greater. Losses 60-80dB operation. The latter may be jigged using a 0.25in drill. (1-100 million times) greater than those over un- Note that the position of the input flange is not critical in obstructed paths are not untypical. In order to work over any way. but that at the oscillator end it should be within these obstructed paths, the overall system gain has to be about 1mm of that specified. correspondingly increased and it becomes necessary to (e) Drill and tap the holes for the matching screw. start counting every decibel. The receiver described Remove the excess waveguide projecting from the flanges below, although it is simple to construct, is intended to be by sawing, filing and finally by grinding on wet silicon efficient at this level. An unusual feature is the flexibility of carbide paper backed by a sheet of glass. Carefully the design. Because of its particular configuration, a small remove burrs from the inside of the guide. especially amount of the local oscillator power is radiated and where the insulation is to be fitted. obviously this can be modulated and used as a transmit- (d) Carefully file away the lip from the mixer diode large ter. By a simple modification the output power can be increased if desired, but at some expense of the perfor- To prea mplifier To Gunn mance of the receiver. and if strip diode power Design and construction supply unit The receiver is shown schematically in Fig I. It consists of a simple mixer assembly which is connected directly to a Gunn oscillator of the type which defines its cavity by an F-4 H To iris. The mixer uses a length of waveguide into which is antenna Mixer Gunn , diodeI cl'oCe All fitted the mixer diode, the hot end of which is decoupled and feeds the If. amplifier in the conventional way. GUNN MIXER UNIT Diodes of the 1N23 type are recommended; those with I I OSCILLATOR later prefixes (E, F. G) are preferred for their lower noise

'Physical Chemistry Laboratory. South Parks Road. Oxford OX I 3QZ. Fig 1. The general arrange ment of the receiver

492 RADIO COM MUNICATION June 1978 BN C socket soldered to wavegulde 6BA matching loner fro m 81BAscrev r.... \ scre w Belling Tag socket 9 to1Omm dia 1 layer of Sellotape DC feed 3/3 2'dia hole

—.5 m m Gunn diode

35//32:16dti° a 2BA bearing nut

2BA lock-nut "Drill and tap 8BA 2BA scre w counterbored with 0.062" dia hole at Brass boss one end from knob PT FE tuning scre w threaded 1/4 "Whit (a) 27 31m m - -4.1 iris plate (c) Maximu m Length X ..... 0•005"ptf e or frequency 'L' Spring-loaded 6 BA or 8BA polythene insulation screws — 5m m pitch GHz m m

9mrndia 10.0 19.8 Tag to 10.2 19.2 1 amp 10.4 18.6 10.6 16.0

For hole di am eter. see text

(D) 27 ±1m m Iris plate Material 20 or 22 swg brass sheet

Fig 2. (a) One form of the mixer assembly (G3 WDG). The single matching screw fits in one of two holes tapped close to the centre line of the guide, with the length M 11m m for 10 0-10 1GHz and lOm m for 10 s-10 4GHz. (b) An alternative configuration for the mixer (G3R PE). The position of the matching screws is not critical: they can be placed any convenient distance from the diode. (c) A modified G8APP design of Gunn oscillator connection (or from the adaptor if the diode is of the Align ment reversible type) so that the connection is uniformly 0-25in The preferred method of aligning the mixer is as follows: diameter. (a) Connect the input of the mixer via a variable (e) Drill the hole in the capacitor plate so that it is a tight attenuator [2] to a suitable rf source, which can fit on the diode pin. When assembling, press the diode conveniently be the local oscillator to be used. Inject rf at against the wall of the guide before tightening the grub signal frequency and adjust the matching screws to screw. maximize the mixer current while, at the same time, The construction of the design given in Fig 2(b) is setting the variable attenuator so that this maximum similar, but in this case the diode is bolted to the by-pass occurs at the optimum value for the particular mixer capacitor at one end, while the other end is made a tight fit diode being used. For point contact diodes, a current of in the wall of the guide. In mixer diodes that are reversible •250-500µA is suitable. The matching screws should then it will be found that one connection pin is solid and, be locked in position. During this operation, the rear end preferably, this is the one that is tapped. The pin is of the mixer cavity should be closed with either the iris to undersized for the 8BA thread specified, so the forces be used or by a blank plate. involved in tapping the thread are small: it can be done (b) With the input connected to a matched load [3], and while holding the diode with the fingers. the Gunn oscillator fitted in its normal position, alter the The fabrication of the Gunn oscillator should present size of the hole in the iris plate until the diode current is the few problems. Constructional details are given in [I] if same as that during (a). Obviously the size of the hole will these are required. The heatsinking in this design is depend on the output power of the oscillator but will certainly adequate for the low power diodes which normally be in the range 3-5mm diameter. generate up to 20m W and which dissipate about I W. It is In an alternative method used by G3WDG, the receiver insufficient for high power devices which dissipate about is assembled with the antenna and waveguide run which is IOW. Note that for many low-power Gunn diodes the to be used. For initial tests an iris about 4mm (3/16in) is connection with the flange should be made negative. suggested. The matching screw (in the appropriate hole in

RADIO COMMUNICATION June 1978 493 •-kii +12V in Fig 2, 27mm, represents a compromise length between 0.3Adc 10.0 and 10.5GHz. It is somewhat smaller than the values calculated for 3Xt/4 at these frequencies, namely 29-8 and 27-4 respectively. The same procedure is recommended if it were desired TO Gunn diode 0.01 201 to optimize the mixer assembly at another frequency. or to lengthen the cavity by making it 9.8/4 or 7X1/4 in order OV to fit a wavemeter. Other Gunn oscillators which employ an iris at the Fig 3. A simple zener diode psu. The working voltage of ZD1 is output flange can be substituted directly. Examples are nor mally 7 9V, see text given in [4]. As noted earlier, some of the local oscillator power is the G3WDG design) is then adjusted to set the mixer radiated from the antenna port and may be used as a low- current at about 250µA. If the current is greater than this. power transmitter. By increasing the size of the hole in the even when the screw does not penetrate into the guide, iris plate the amount radiated may be increased to make then the iris should be reduced in diameter. Conversely, if the transmitter more effective. although the reduced Q of the mixer current obtained with up to the maximum the oscillator cavity resulting from this change means that recommended penetration of 3-4mm is still less than the the efficiency of the receiver will be impaired. Despite this. optimum value, then the size of the iris should be the performance of such equipment should be com- increased. If the size exceeds 6mm. then there is a risk that petitive with that of most other transceiver configur- the stability of the Gunn oscillator might be adversely ations. The size of the iris should not exceed about 6mm affected. If the mixer current is still too low. then a fault in diameter, otherwise the stability of the Gunn oscillator construction, a poor mixer diode or a badly-matched may be seriously affected. antenna should be suspected. The latter can be checked by substituting a large horn (or any other well-matched load) Power supply unit for the antenna in question. If correct operation is The simplest practical psu consists of a zener diode obtained, then the matching of the original antenna stabilized circuit as shown in Fig 3. If. as in this case, the should be improved using, for example, another set of receiver local oscillator is not to be modulated, then the • matching screws fitted to the antenna. working voltage of the Gunn diode will be close to that which produces maximum power output. This can be Alternative configurations checked by operating the oscillator via a variable resistor The critical dimension of the mixer assembly is the length (eg 47S2 3W) from a 12V 0-3A dc supply. and using the of the guide between the diode and the iris. This was mixer diode current as a power indicator. A zener diode of determined experimentally by fabricating an adjustable the optimum working voltage and I W rating can then be iris from 0.02in thick sheet 0.9in wide which was bent into fitted, and the value of resistor R set so that the zener the form of a square "U" with the base 0.4in wide. Using diode passes 50-100mA with the Gunn diode connected. the set-up described under Alignment (a), the position of It is of advantage to be able to frequency modulate the the iris, the penetration of the matching screws and the receiver local oscillator with tone since this enables cw insertion loss of the attenuator were adjusted at signal signals to be detected. If there is a chance that the unit will frequency to peak at the optimum current for the mixer be used as a transceiver, if only as a low-power spare diode. It was found that moving the iris away from its best equipment, then it is worthwhile also to build in speech position by up to about I mm could be compensated for modulating facilities. A recently developed circuit pro- by readjustment of the matching screws. The value given duced by G8AGN/G8CZO is given in Fig 4. A deviation

+12V unstabilized To Gunn dlo e 0 7805 C e I 100 3.3k

15k 04 7 1 - o 10k o Set deviation 0.01 1 15k 100k 2 20 Tone generator l S k 4.7 Crystal et Fig 4. A modulated psu which microphone 1. Volts is due to G8 A GNI/G8CZ O tBk

47k

Key _ 10 1M '0 741 = 0.22 0.47 - '-

Set — 0.01 speech deviation ampli her 100 T 3.3k

494 RADIO COMMUNICATION June 1978 of about 100k Hz is usually employed, this being suitable A useful check on the overall performance of the for standard broadcast fm components. receiver is to measure the difference in its noise output when the antenna is pointed at the sky or at objects such Receiver preamplifier and i.f. strip as the ground. This technique is described briefly in [6]. One of the advantages of having a separate receiver is that there is a wide freedom of choice for the i.f. frequency. In References fact almost any frequency can be used in principle since its RC' = Radio Communication: Al = RSGB VHF/UHF value will be taken into account during the final Manual. 3rd edn. calibrating process. With single-ended mixers of the type described above, there are advantages in using a relatively [1] RC February 1976, p123. high if. in the region of 100MHz. A convenient form for [2] RC December 1972. p280: also M. Fig 8.39. this can be a standard fm broadcast receiver, which may [3] RC November 1972, p74I also M. Fig 8.36 and 8.37. have limited afc facilities built in—as well as a tape Horn antennas normally represent a well-matched load. recorder. Some receivers of this type can tune 150MHz. [4] RC May 1974, p288, Figs 6, 7 and 8. Figs 7 and 8 are which is a useful i.f. in that the receiver can be made to also shown as Figs 8.52 and 8.53 in M. Also RC tune 10.000-10.100MHz on one channel. and September 1976. p667. Figs 1 and 2. 10,300-10.400MHz on the other. Suitable preamplifiers [5] M. Figs.8.74-8.78. using either BFY90 or 40673 devices are given in [5]. [6] RC July 1977. p54I.

Front Modifications to the Functron L9 v FO board Yaesu FR5OB receiver 0 0 o L19

by E. ELSLEY, G3YUCr CO:I s LI LB LIJE o[iovpo V4 V3 N his quest for a simpler approach to amateur radio. Ftlter 1 the author has exchanged his FRDX400 receiver for an see detall FR50B/FL50B receiver/transmitter combination. These Ma.ns two units perform very well together, using the FR5OB transformer 2 x 1/4 -dla holes vfo to give transceive operation. No modifications to the for coaxial cables.\,,,C)IF trap FL5OB transmitter have been found necessary. The FR5OB receiver can, however, be very much 00 improved by a couple of simple modifications, and this Rea r Antenna socket article gives details of changes which will improve the Fig 1. Under-chassis layout of the FR506 selectivity and cross-modulation performance. The author realizes that most amateurs are reluctant to modify their equipment. especially when it may affect its receiver from the cabinet by removing the four self- resale value, but these modifications can be removed and tapping screws from under the set: the receiver can then the set restored to its original specification very quickly if be withdrawn from the back of its cabinet. Locate the required. filter (see Fig 1) and disconnect the input and output capacitors C28. C29. and the earth from the ceramic filter Selectivity pcb. Next, remove the two self-tapping screws which The FR5OB uses a two-stage ceramic filter in the i.f. strip secure the board to the chassis, and remove board to and, while this quite simple arrangement gives good expose an oblong hole in the chassis. Drill out to 6BA the selectivity, it can be further improved by replacing it with a good mechanical filter. The author used a Kokusai Screen MF455 10k unit, obtained secondhand without carrier V4 V3 6BA6 crystals (not required) for £10. The Kokusai MF455 15k 6C B6 BC5FIs filter is equally suitable and, as its bandwidth is slightly I z b, X 5 greater than the 10k unit, it could possibly be better, 1 B o giving a more natural quality to the signal. ° 0 G PU Fitting the filter is very simple. First, remove the C29

•14 Studley Road. Wootton, Beds. Fig 2. Detail of filter installation

RA DIO CO M M U NICATIO N June 1978 495 Coaxial lead to Coaxiai 7- Material.. 16swg aluminium antenna lead to 114 sheet terminal i f trao

2 fixing holes are Bend up at 90. 6BA clearance •

Fig 3. Screen for filter Resistors are 1/4 watt rating two holes used for the self-tapping screws, and lower the Fig 5. Attenuator for the FR508 Kokusai filter through the chassis with terminal P facing V3 and terminal G facing V4, as shown in Fig 2. Place the screen across the bolts (Fig 3) and secure to the chassis the coaxial cables from the underside of the chassis it is with the nuts provided. Connect C28 to terminal P. and necessary to drill two in holes near the i.f. trap, as shown C29 to terminal G. Terminals E and B are connected to in Fig I. earth via a short lead. Check that the connections are as The panel marking can be changed by using the covet shown in Figs 2 and 4; note that the component numbers plate shown in Fig 6. The plate is made of thin aluminium are as shown in the Yaesu handbook. and finished by brushing across with sand paper. It is then Switch on the receiver and allow to warm up. Set lettered up using Letraset or similar transfers. If using function switch to a.m. and bandswitch to 3.5MHz. Letraset, the best type to use is Folio Medium 14pt Switch on the calibrator, adjust the tuning to zero, and 3-8mm. which almost matches the FR50 lettering. The zero beat with the calibrator to give a reading. Adjust the plate is held in position by the switch fixing nut. cores of L6, L7, L8 and L19 for maximum reading; note that L6, L8 and L19 have cores at top and bottom. Set the bfo pitch to 456.5kHz. Then set the function switch to ssb, and adjust the top core of L9 for clear ssb reception. Seal all adjusted cores with a little candle wax. The modification is now complete. and on tuning ATTENJATOR across the band the improvement in selectivity and signal 2 7/4: to noise ratio is most noticeable. The bfo pitch control • 3 does not require adjustment when changing band but may be set to 453.5kHz to receive the opposite sideband if o required. A little adjustment may be necessary as the set 5/e*raci warms up. as the bfo on the FR5OB does drift a little. Material.... 3 /8*cl i a 205w9 hole aluminium sheet Cross-modulation The FR5OB receiver suffers from cross-modulation, and the author experimented with various attenuators to try to cure the problem. The final circuit used is shown in Fig 5. No originality is claimed for the circuit, which is based on one obtained from Amateur Radio Techniques 5th edn, Fig 8. Cover plate for attenuator control p70. with a modification to switch position 5 on the original circuit. The front panel of the FR5OB has a control marked CH The results of this modification are quite noticeable. In SELECT which is not used, having a dummy control at the the evenings, on 7MHz, with if gain at maximum and no rear to hold the knob. This is removed and replaced by a attenuation, the band is just noise; reducing the rf gain two-pole five-way wafer switch on which the resistors are reduces the noise. However, with full rf gain and mounted. Coaxial cable is taken from the antenna socket maximum attenuation (position 4), signals can be picked to the switch, and from the switch to the if. trap. To bring out with ease.

Conclusion Kokusai filter (underside view) These simple modifications have, for quite low cost, iScreen V3 C28 C29 V4 changed the performance of the author's FR5OB receiver 6BA8 6C136 I--OP into the de-luxe class, and are well worth the little time 100p çs. 100o spent on them. E As mentioned earlier, the receiver can be restored very R1S R21 68k 68k quickly to its original state, leaving only two small holes in the chassis. To ht To a v c The author will be pleased to hear from anyone trying out these modifications, and will help with any queries Fig 4. Circuit diagram of connections to Kokusai filter for the FR608 (sae, please).

496 RADIO COMMUNICATION June 1978 1 C3 An afterburner T =op T'''' RFC2 C5 rrin TRI L2 L3 0.01 CI BLY83 3 to3Op for the LI RLAI RLA2 To set To antenna 4 eC5 G3TDZ fm 0RFC1 7 1 to 30p black box

by J. R. HEY, Tech (CEI), MSERT, G3TDZ'

RLA or '07— —irdo ordq, N retrospect it was inevitable that another 1W rig from 2 L \ozol 1 the 'TDZ stable would provoke a demand for more power by would-be constructors. A simple add-on power amplifier which could easily be adapted for fixed station or mobile use seems a worthwhile venture. While most amateurs have few inhibitions when throwing together a thermionic amplifier, experimen- Fig 1. Circuit diagram tation with solid-state rf power is met with rather more caution. The single transistor amplifier offered here may be employed as an add-on for a number of different piece screws onto the transistor stud and to the chassis, transmitter conditions; Table I shows coil winding data forming, with the copper surface, an adequate heat sink. and trimmer capacitances under various loading For simplicity, a relay is used to couple in the amplifier conditions. when on transmit. The first fact one must face with rf power devices is the Fig 2 shows the pcb layout and component mounting gain one might expect. While quoted gains of individual positions. Chassis details are left to individual choice. D transistors listed in data sheets vary from as low as 4dB to over 10dB. a fair rule of thumb is to think in terms of 6d B. ie a four-fold increase from a single stage. Table 1 The circuit of Fig I employs a "turnstile" transistor Condition L2 13 C6 C7 4W. 12V. 5012 0-145pH 0.135 0 24pF 44pF type BLY83. With a 12-13.5V supply, a power of 7W may 8 turns 7 turns be realized, and I 3W when using a 24-28V supply; the 4W, 12V, 750 0.145pH 0.148pH 23.6pF 34.5pF drive level necessary however is 1.35W. One watt from the 8 turns 8 turns 'TDZ black box produces just over 4W from a I 2V rail. 7W. 12V. 5on 0.12pH 0.125pH 20pF 40.65pF 7 turns 7 turns The rf circuitry is laid out on a single-sided copper 7W, 12V, 7511 0.12pH 0.145pH 19.6pF 31.8pF laminate, copper side uppermost. All connections are 7 turns 8 turns soldered directly to the copper, but the mounting holes 13W. 24V. 500 0-165pH 0.15pH 14-8pF 35.8pF 8 turns 8 turns may be used for guidance if desired. Oxley type trimmers 13W, 24V, 7511 0 165pH 0.165pH 14.4pF 29-2pF were fitted in the prototype. A threaded spacer or distance 8 turns 8 turns All coils are in id air-spaced. self -supponing, 20swg copper. '8 Armley Grange Creseeni. Leeds LSI2 L1 is in long. and 1.2, L3 in long. (Mounting holes, Fig 2)

Input 5' x 1.5" Actual size Antenna

Tinplate screen 1/2'high RFC1

Fig 2. PCB and component layout

HT+

RADIO COMMUNICATION June 1978 497 transponder would periodically switch itself back on. The University of and. as Oscar 6 did not have a positive power budget. this latter occurrence was potentially dangerous. The 435M Hz beacon pa went short-circuit soon after launch and. if this switched itself on. excessive battery discharee Surrey AMSAT resulted.

UoS-A MSAT telecom mand Because of these problems t became of paramount telecom mand centre importance to establish a global chain of command stations to ensure that Oscar 6 was maintained in the correct mode at the correct time. To provide European coverage the simplest possible automatic command by M. SWEETI NG, BSc, G3YJO' station was quickly set up at the University of Surrey. using low power. fixed beam headings and pre-recorded command tapes. while work on a more sophisticated. W OUR years ago this month UoS-AMSAT was formed long-term project got under way. to provide a permanent European control station for An old Bofors gun mount, modified to carry a 2m dia the amateur satellite Oscar 6. The aim of this short article parabaloid. was acquired from ASWE. cleaned up and is to outline the reasons for which the station was placed on top of the tower above the radio room. The established, what it achieved, and its future role with tracking mount weighs 3! tons, and is driven by two 30V. Oscar 8 and beyond. 30A dc motors capable of providing a maximum az/el (azimuth/elevation) slew rate of 60°/s. The original Problems with Oscar 6 control equipment, using metadyne generators, was far Soon after launch. Oscar 6 exhibited a fault which too bulky and extremely noisy. and so was replaced resulted in random mode changes. Variations in solar entirely by a solid-state control system. The determin- array currents, due to the toppling motion or the ation of the transfer characteristic of the mechanism, the spacecraft moving in or out of sunlight, induced spikes design, construction and testing of the prototype power into adjacent switching logic lines, causing a change of and control electronics was carried out by students and status. The most important of these random mode completed in five months. changes were those resulting in change to the status of the Antennas for the 144. 432. 1.300 and I 37MHz transponder or 435MHz beacon. When scheduled ON. the satellite bands were mounted around the dish (which has transponder would suddenly switch itself off with some a lOGHz feed for terrestrial amateur colour tv experi- inconvenience to the users. When scheduled OFF. the ments). A high-power command pa and a digital command encoder were constructed alongside the development of computer programs to provide accurate az/el *Dept of Ek.•eironie and Electrical Engineering. UoS. Guildford. Surrey predictions for every visible orbit. The final program. run GU25XH. on the university's main ICL I 905 computer. produced

Command centre showing (I to r): autocom mand logic, aziel control and Oscar 8 command encoder (in panel), and the on-line facility to the ICI 1905 and (on right) the author at the communication equipment controls

Photographs (including front (W M' ht. l'oS .4utlio I 'imal l id Unit

498 RADIO CO M MUNICATION June 1978 Fig 1. Oscar 6 battery voltage as a function of orbit number during the last 18 months of the satellite's life

data which, when loaded into the autocommand logic on broadcasts and Oscar 6-Oscar 7 intersatellite links) paper tape, switched on the power amplifier to warm up were all switched automatically. 5min before aos (acquisition of signal); controlled the The full autocommand facility was commissioned in antennas to track in az and el throughout the orbit: and August 1976, and the immediate effect on the battery switched on and off the command transmitter, having discharge level can be seen in Fig I. which shows the on- selected the appropriate command sequence scheduled board nicad battery voltage ata function of orbit number for that particular orbit. At los (loss of signal) the station during the last 18 months of the spacecraft's life. shut itself down and waited for the next orbit. The The eventual decline and fall of Oscar 6 is also well autocommand data was reloaded every 10 days and, in demonstrated in Fig I. In January 1977 the orbit was in the meantime. the station required no attention— almost total sunlight and the nicad battery was getting theoretically. Special test orbits (HG5BME news very hot indeed: further aggravated by I2R losses in the

Fig 2. Oscar 6 battery temperature during the same period as Fig 1

RADIO COM MUNICATION June 1978 499 battery as the internal resistance of the cells increased with old age. Fig 2 shows the battery temperature during the same period (Note that the higher the telemetry count, the lower the temperature). The excessive battery temperature accelerated the deterioration of the battery as cell after cell failed (short circuit), and the bus voltage dropped accordingly. Even the gradual cooling of the battery in March-April 1977 did not halt the decay. In June the telemetry indicated a dramatic drop in voltage, and then finally became garbled. Two weeks later the transponder fell silent.

W eather satellites The interval between the demise of Oscar 6 and the launch of Oscar 8 provided a breathing space to update the UoS station and to build up some equipment for the. reception of the NOAA-4 and 5 meteorological satellites. Daily cloud-cover pictures were taken until the failure of the NOAA-5 instruments in March 1978. Several spacecraft in the Nimbus and (Russian) Meteor series are also periodically observed.

A MSAT Oscar 8 Oscar 8 was launched from the Western Test Range at Lompoc, California, on 5 March at 1754 and was ejected from the second stage of the Thor-Delta launch vehicle at 1919 over Greenland. The 435.1MHz beacon was heard at UoS for a few seconds after ejection and before the Operators (I to r): G8N1L0 (Key), G4EDVV (Paul), G3YJO (Martin), G8JFX (Tim) and G4CWH (Colin) on the roof of the spacecraft dropped below the Arctic horizon. On the university with the antenna mounting in the background. following orbits, downlink telemetry and doppler Other operators, not sho wn, are G8NEF and G8NEH measurements were taken and the command functions checked out. The data, including telemetry from other UK stations, was collated and transmitted from UoS to Conclusions AMSAT-USA at the Goddard Space Flight Centre via an By meticulous control UoS-AMSAT helped to extend the excellent 28MHz link and later via direct landline. operational life of Oscar 6 by an estimated one year. During the two-week evaluation period, before Oscar 8 During that time some seven million commands were was handed over to the ARRL, UoS-AMSAT Telecom- transmitted and the station was operational for 24h, mand carried out an extensive series of command and seven days a week. Three breakdowns were experienced— communication experiments — the results of the latter two due to fan failure and one due to mains failure, in showing the transponders to have excellent sensitivities. each case the station was in operation again within 6h. UoS-AMSAT will now liaise with the ARRL to maintain A comprehensive amateur groundstation facility has the operating schedule for Oscar 8, and will continue with been established in the UK as a result of the shortcomings telemetry retrieval and analysis as well as command and of Oscar 6. Continued work with Oscar 7, Oscar 8 and communication experiments. meteorological spacecraft, in conjunction with the planned flight hardware, not only provides a useful contri- In the future bution to the AMSAT programme in general, but also a Apart from the surveillance of Oscar 8, UoS-AMSAT is valuable educational and research tool within the UK. developing an 8080 microprocessor-based autocommand system, designed to replace the somewhat inflexible ICL1905 + logic presently employed. The microcom- Ackno wledgements mand system should enable more extensive use to be In this brief review it has been possible to describe only made of the Oscar 7 codestore facility, and should also the barest bones of the University of Surrey AMSAT result in improved command efficiencies for Oscars 7 telecommand centre activities, which would not have and 8. been possible but for the very considerable assistance of Modifications to the meteorological satellite downlink the university authorities, especially Professor D. R. equipment are under way to enable it to receive Chick and members of the Department of Electronic and transmissions from Tiros-N, due for launch later this Electrical Engineering. Many industries and concerns, year, and also from the geostationary Meteosat. notably: ASWE, STC, ITT. SMC, Western Electronics, Preparations for the Phase 3 (elliptical orbit) spacecraft Microwave Modules, Storno, Plessey and others have have started, and plans for a space hardware team at UoS generously supported its activities. Thanks are also due, are also under discussion with a view to a UK contri- not least of all, to the students who devoted an enormous bution in flight hardware to the AMSAT programme. amount of time and effort in building up this facility. I::

500 RADIO COMMUNICATION June 1978 although generally the bigger the better. An hour or so spent on the original design data will give an idea of what nnicrowaves is required. (b) An important advantage of this antenna is that the component mounted at the top of the mast is only a flat Charles Suckling, G3WDG * sheet. Perforations can be made in the reflector, provided that the diameter of the holes is less than X/10, and these will reduce windage at low wind speed. To cope with worse weather, G3JVL's reflector is pivoted just in front of its centre of gravity, so that it will "feather" in high Winchester round table winds. This means that a fairly large reflector can be used About 80 people attended the latest microwave round with safety. The use of a parabolically curved reflector is table meeting, which was held at IBA Engineering HQ, not recommended, as the increase in gain possible with Crawley Court. Visitors included DL3ER from Munich. this type of reflector is hardly worth the difficulties in its and ZL3TCB/G800K. In the morning session G3RPE manufacture. The reflector at present used by G3JVL is a discussed the preparations which were being made by the perforated flat steel sheet. 3Iin by 48in, which is stiffened Microwave Committee for the Hungary IARU con- by ribs soldered to it. A coat of paint reduces the rate at ference and for WARC 1979. G4CNV then outlined the which it rusts. committee's proposals for a new set of microwave (c) The mast system used to support the antenna must operating awards (see below), which were received be vertical to within a small fraction of a beamwidth, je a enthusiastically by the meeting. G3WDG continued the few degrees at lOGHz. The reflector does not have to be at discussion by outlining the rules for the forthcoming exactly 45° to the mast if the position of the feed can be microwave contests. The subject of talkback was raised. adjusted to suit the actual angle. and from the discussion which followed it soon became (d) The antenna would seem to be useful also for clear that most stations would be using 144-33MHz ssb. portable work from sites where there are local obstruc- or 433.2MHz fm; a few even favoured I44MHz fm! In tions, especially because there is no feeder cable or general it seemed that horizontal polarization would be waveguide to get mixed up with the guys. used on I44M Hz. and vertical on 432MHz, but that this Once again, thanks are due to Don and Anne Hayter would not be universal. It was suggested by G3WDG that for organizing a most enjoyable event. preferred polarizations, as well as frequencies, be included in the information sheets, so that people would at New micro wave operating awards least know what was in use. G8AGN then gave a brief report on some work he is The current set of microwave operating awards is in the form of certificates issued for a station's first contact doing concerning the prediction of duct formation from beyond 600km on I.3GHz, 500km on 2.3GHz, 400km on available meteorological data. Preliminary results seem to 3.4GHz, 300km on 5.7GHz and 150km on 10 and 24GHz. indicate that ducts capable of propagating microwave In order to recognize regular consistent operation, the frequencies are surprisingly common. To test his theories Microwave Committee has proposed two new awards, a he has analysed a considerable number of duct-assisted QTH-locator based award and a counties-plus-countries contacts, and he has found that the enhanced propa- award for each band 1-3-24GHz. Both awards will apply gation conditions which made these contacts possible to stations operating portable or from home, although corresponded well with the predictions. In this context only one site may be used (a site is defined as anywhere G8AGN would like to receive as much information as possible about any tests made above 1GHz (whether within 5km of a fixed point). The QTH-locator award will be progressive, the lowest successful or not) since 1971, using super-refraction or category being issued on receipt of proof of contacts with tropospheric propagation. Further work should show stations in five different large QTH-locator squares, eg whether his method is likely to prove useful enough in ZI... AM etc, and additional stickers will be given when predicting good propagation conditions on a regular further multiples of five squares have been worked, je 10, basis, and this would obviously be of great interest. 15, 20 etc. In the afternoon session G3JVL dealt with the practical realization of an efficient flyswatter antenna system. In the The counties-plus-countries award will be the same as that currently issued for 1-3GHz. ie 20 UK counties plus 3 basic design a plane or parabolically curved reflector is countries (including the county and country of oper- mounted at an angle of approximately 45° at the top of a ation). Counties will be defined as those existing at the mast. A feed dish nearer ground level, where the rf- time of introduction of the award. Both types of award carrying components are mounted, is arranged to point will be retrospective, so that existing achievements can be vertically upwards at the reflector, which reflects the recognized. signals in a horizontal direction. The general design of It is felt that these awards will represent something for this antenna is described in the August 1977 issue of Radio Communication. G3JVL made the following important everyone to aim at. The level of difficulty is quite different points concerning the implementation of this system. for the two awards; for example, five QTH squares on 1-3GHz is quite easy, while 20 counties plus three (a) The overall design of the antenna is remarkably countries will be a considerable achievement on the higher uncritical. Any size of reflector and feed will work, bands, although not impossible given several years of consistent operation using state-of-the-art equipment. The writer would be very pleased to receive any •Ph>mcal Chunnstrs Laboratory. South Parks Road, Oxford OX1 3QZ. comments on the above proposals. El

RADIO COM MUNICATION June 1978 501 with amateurs in all countries. Obviously, this is a very Visiting the USA as simple procedure, and is just what the visitor desires. To be eligible, an amateur must be a citizen of the country that issued his licence, and that country must have a reciprocal agreement with the USA. Wan amateur an amateur radio is not a citizen of the country that issued his licence, even if his own country has a reciprocal agreement with the USA. he does not qualify. If an amateur is an American operator citizen (perhaps through dual citizenship). he may not obtain a reciprocal licence, even if he meets the first requirement. All is not lost, however, since anyone who by BILL JOHNSTON, N5KR• • does not meet the eligibility requirements for a reciprocal licence can still obtain a regular USA licence simply by passing the appropriate examination once he gets to the VERY year millions of visitors come to the USA, and USA. More will be said about that later. There is only one Eamong them are many amateur radio operators who minor exception with regard to eligibility, and that is a would like to operate their radio equipment while here. person who is a "foreign government, or a representative Unfortunately, many foreign visitors are confused as to thereof-, who is not eligible for either a reciprocal licence whether they may obtain a permit to operate, and if so, or a regular USA licence. (No one the author has talked to what procedure is to be followed. Since Radio Com- seems to know just who might be a "foreign government, munication is probably the most widely read amateur or a representative thereof- , but he is told that "if you are radio publication outside the USA, this seems to be the one, you will know it".) If one has any doubts, there is a appropriate place to explain the simple procedures space on the application forms for comments. whereby any foreign amateur may operate his equipment Let us assume that one qualifies for a reciprocal licence (or ,that of another amateur) during his visit. The to operate in the USA. What must one do to obtain it? information presented here applies to all W. K and N call First get a copy of the correct form —FCC Form 610-A. areas, including-Hawaii, Alaska, Puerto Rico, and most Copies are available from the FCC's main office and its of the Pacific islands under American administration. various field offices, though a heavy workload may delay First of all, any person, whether he has an amateur the response. If one is in a hurry, it is better to request a licence or not. may visit the station of an American copy of the desired form from the A RRL at: In- amateur and participate in the activities of the station. ternational Services Desk, American Radio Relay Lea- The visitor may speak over the microphone, and/or gue, 225 Main Street, Newington, Connecticut 06111, operate the morse key, teleprinter keyboard, or even a USA. A self-addressed airmail envelope and a couple of television camera. The station licence-holder must be IRCS would be appreciated, but this is not mandatory. present, however, to operate the radio equipment itself, Once the form is completed. a photocopy of the and it may only be operated in the bands that the class of applicant's own licence should be attached, and the his personal licence allows. Furthermore, and this is very application sent to the address given on the form at least important, such operation can be carried out only in two months in advance of the visit, but preferably three or contact with other USA stations, or with stations in four months ahead. The licensing delays at the FCC, countries which have a third-party agreement with the caused by the cb boom in the USA. still exist, and it is USA (the visitor is the third party in this case). Although better to be safe than sorry. There is no fee or charge for the USA has third-party agreements with most countries the licence. in North and South America, outside this hemisphere it The application form requires certification that the has such agreements with only three countries: Israel, applicant is familiar with Part 97 of the FCC regulations, Jordan and Liberia. So one can see that such operation is a copy of which may be obtained, at a small charge, from restricted, and not all what the average travelling the USA Government Printing Office in Washington DC. amateur has in mind. However, to be quite frank, it will probably arrive after the visit is over. A much better investment is a copy of the Radio Amateur's Licence Manual which can be obtained Obtaining a reciprocal licence from the ARRL. at the address listed previously, for $3, The USA has reciprocal licensing agreements with more postpaid by surface mail. It contains a complete copy of than 50 countries (including the UK), and radio amateurs the regulations, plus a plain-language explanation of the who are citizens of these countries may obtain a permit major points. A complete listing of the American band from the Federal Communications Commission (FCC) limits is given, along with a detailed listing of the types of by simple application. A complete list of these countries is emissions permitted within specific sub-bands. The included in the appendix. With a reciprocal licence, the remainder of the book deals with how to prepare for the foreigner has full operating privileges while in the USA, exams for a regular USA licence, so those parts will not whether it be with his own equipment, borrowed concern applicants for reciprocal licences. equipment, or while visiting the station of another The reciprocal licence is normally valid for a period of amateur. The operating privileges are equivalent to the one year, unless one's native licence expires sooner, in Extra Class licence (the highest USA licence), and one which case the reciprocal licence expires at the same time. may operate equipment accordingly, and communicate It may be renewed as often as necessary. but application for renewal should be made at least a couple of months in

•1808 Pomona Drive. Las Cruces, New Mexico 88001, USA, advance. Aliens who will be living in the USA for an

502 RADIO CO M MUNICATION June 1978 extended period are encouraged to obtain a regular USA the USA must give his approximate location once during licence by taking the exams. each QSO; saying something like. "I'm in Plains. Assuming the reciprocal permit has been received, one Georgia", or "I'tn a few miles east of Apache Junction. may begin operating immediately on entry to the USA. Arizona". is perfectly acceptable. Remember, however, that while over here the visitor must abide by the USA regulations. though having full USA Obtaining a regular USA licence privileges. A point to be especially careful about is to What happens if one does not qualify for a reciprocal remember that American phone sub-bands are somewhat licence? A regular USA licence may still be obtained more restrictive than those of most other countries. simply by passing the appropriate exams. In this case one Having a copy of the A RRL's Radio Amateur's Licence will receive a regular USA callsign and operate just as any Manual on hand will give quick answers to any questions other American amateur. Anyone may obtain a licence in that might arise. this manner, regardless of nationality, even if one's own The only way a foreign amateur's operation will differ country does not extend the same courtesy to Americans, from that of an American amateur is in the manner of and even if one qualifies for a reciprocal licence. There is identification. A foreigner's identification consists of his only one exception, as in the case of the reciprocal licence, own callsign. followed by the word "portable" or one must not be a "representative of a foreign govern- "mobile", as appropriate, followed by the prefix of the ment". At the present time, there is no fee or charge for USA callsign area from which he is operating. For the licence, and it is valid for five years. It is renewed by example. on phone one might say. "G4X YZ portable simple application. W4", "XE I XY mobile KL7". etc. On cw or rtty, these As the licence being talked about is the standard US would be "G4XYZ/W4" and "XE I XY/K L7". licence, this is not the place to discuss it in detail. Suffice it respectively. to say that there are several classes of licence which There are no restrictions as to the type of mobile convey greater privileges, obtained by passing exams of operation permitted. and one simply says "mobile" greater scope and difficulty. There are 28 cities where the (though one may be more specific if desired), whether in a exams are held at least once a week, and 72 additional car, on foot, in an aircraft, in a canoe, or hanging from a cities where exams are held two or more times per year—a parachute (the author does them all). Also, do not forget total of 100 cities where the exams may be taken. If one that in a boat (or plane) on entering international waters fails, 30 days must elapse before resitting the exam. If one one is obviously no longer in the USA. and jurisdiction passes, the licence should arrive within 8 to 12 weeks, and immediately reverts to one's own country. Incidentally, one must wait until it arrives before going on the air. amateur operation on an aircraft requires advance The ARRL Radio Amateur's Licence Manual gives approval from the captain, which is fairly difficult to complete details on the privileges conveyed by each class secure on a commercial airliner, so most aeronautical of licence, as well as study material appropriate for the mobile operation is done in private aircraft. various exams. 73 magazine publishes several excellent Probably about one out of every three American books for use as study guides. For more information, see amateurs will say that the use of the letter W as part of the any recent issue of the magazine, or write to the publisher portable identification is unnecessary. This is entirely at: 73 Radio Bookshop, Peterborough, New Hampshire incorrect. As an example, "XE1XY/2" would signify that 03458, USA. XEIXY was operating portable in the second district of Mexico, whereas "XE1XY/W2" shows that the portable W hat equip ment to bring? operation is in the second district of the USA. Con- The author is a firm believer in travelling light—it saves sequently, the use of the letter W is required by regulation energy. and trouble with customs. If one wants to meet for reciprocal licensees. American amateurs, the ideal piece of equipment to carry If one visits an American amateur, simply use his is a small synthesized 144MHz fm rig: it is estimated that callsign while operating his equipment; he does not have there are more than 4,000 operational repeaters in the to be present if one has a reciprocal licence. However. USA. and almost every American amateur is active on the there is a complication if operating the equipment in a band so one cannot go wrong with a I44MHz rig. There is sub-band that the host's own licence does not permit. no publication which lists all USA repeaters and their Remember that with a reciprocal licence one has full frequencies, but the book Repeater A dos ($1.95 from the privileges. so if the licence of the host is any class other 73 Radio Bookshop), and the A RRL Repeater Directory than Extra Class, one's callsign must be added to his. For (free but you must send 3 IRCS to cover the cost of postage example. on cw it might be "W5XYZ/G4XYZ/W5". On by surface mail) are both good investments. Most phone this is usually spoken as "W5XYZ slant G4XYZ repeaters in the USA are "open' repeaters. where visitors portable W5". That is a QSO in itself! are welcome, and are simply keyed by the input carrier, If a foreign amateur is using his own equipment, or requiring no special tone or code. Do not worry about the equipment borrowed and used away from its home relatively few "closed" machines. station, he should always use his own callsign. In any case, If a synthesized rig is not available, a multi-channel one is required to give the callsign only at the beginning hand-held is the next best thing. The only problem is that and end of the QSO, and once every 10min if the QSO USA repeaters operate primarily in the I46-148MHz lasts longer than that. segment, not common to IARU Region 1, so a sizeable The required identification must be made in English, expenditure for new crystals would be necessary. In any though it may be repeated in another language if desired. case, the most common repeater frequencies (low in, high The QSO itself may be in any modern language. Also, the out) are 146-16/-76. -22/-82, •28/-88. .3404; the most foreign amateur operating under a reciprocal licence in common fm simplex frequencies are 146-46 and 146-52.

RADIO COMMUNICATION June 1978 503 Better than bringing one's own equipment would be to Sum mary make advance arrangements to borrow a rig from a friend Obtaining a reciprocal licence in the USA is a simple in the USA. Long-time friends on the air should be willing matter, and those few who do not qualify can still get a to lend something suitable for a visit. regular USA licence by passing the exams. There is no As far as the hf bands are concerned, the author's charge for the licence. A visit to the USA can be much personal opinion is that one should leave the hf gear at more interesting if a 144MHz fm rig is used, so one can home and do low-band operating during visits to other meet American amateurs on thousands of repeaters stations. At the very least, one would want to carry only a across the country. Be sure to give the author a call on the small, light-weight solid-state rig. Remember also that the way through New Mexico! USA is a very large country, with almost as many amateurs as the rest of the world combined, and dx operating is usually more successful from one's own country. Appendix. Countries which have reciprocal There are a couple of other vhf bands which might be licensing agreements with the USA interesting if one can obtain the loan of suitable Antigua, Argentina, Australia. Austria. Bahamas. Barbados. Belgium. equipment. The first of these is 50 to 54MHz, an Belize, Bermuda, Bolivia. Brazil. British Solomons, British Virgin extremely interesting band inclined to very long distance Islands, Canada, Cayman Islands, Chile, Colombia. Comoro Islands, E-layer openings, which is not available in Region 1. Costa Rica, Denmark, Dominica, Dominican Republic, Ecuador, Eire, El Salvador, Falkland Islands. Fiji. Finland, France, French Antarctica, Most activity is on ssb in the lower half of the band, with French Guiana, French Polynesia, Germany, Gilbraltar, Gilbert and considerable fm repeater and simplex activity in the upper Ellice Islands, Grenada, Guadeloupe, Guatemala, Guyana, Honduras, half. Another band is 220 to 224MHz, which is not Hong Kong, India, Indonesia, Israel. Jamaica, Kuwait, Line Islands, Luxembourg. Martinique. Monaco, Montserrat, Netherlands, Nether- available in either Region 1 or Region 3 (or for that lands Antilles, New Caledonia, New Hebrides, New Zealand. Nica- matter, even in many parts of Region 2). Most activity on ragua, Norway. Panama. Paraguay. Peru. Philippines, Portugal, 220MHz is fm (repeater and simplex), and activity is Reunion, St Helena, St Lucia, St Pierre and Miquelon, St Vincent, heaviest in the larger cities. This is a band where building Seychelles, Sierra Leone, Surinam, Sweden, Switzerland, Trinidad and Tobago. Turks and Caicos, United Kingdom, Uruguay, Venezuela, antennas is actually fun! The 70MHz band is .not Wallis and Futuna. (Additional countries are added from time to time. available in Region 2. Check a recent OST for an up-to-date listing). D

Observing radio

satellites

by P. T. GREED, G3M QD•

N active radio club has been operating since the early A 'sixties, under the callsign G3PZV, from The Head- lands School, Swindon, but it was not until the late 'sixties that an attempt at monitoring satellite frequencies was made, and this resulted in a group being formed for the sole purpose of radio satellite "observation". The enthusiasm with which the students greeted this new venture was extremely rewarding and there developed keen The receiving equipment used by the group rivalry between individual sub-groups, each adopting its own satellite, to see which could make the most accurate The group uses an adapted Drake 2B receiver for the hf predictions over greater and greater time intervals. signals, and precedes it with a converter for the vhf From small beginnings the group has developed its own signals. A general purpose dipole is used for most methods to determine some of the major orbital para- reception, as a highly directional antenna array can be a meters upon which to base predictions. and it now carries disadvantage when one is "searching" for satellites. out three types of observation: New students to the group are involved immediately in (i) recording the acquisition of signal (aos) and loss of general monitoring, and a record is kept of all obser- signal (los) of satellite signals; vations under the sub-headings: (ii) the measurement of the doppler shift produced by the satellite's motion; Date Frequency Time of aos Time of los Observer/s. (iii) decoding the telemetry. What might at the time seem an insignificant observation may well have extreme significance on later • 18 Nursfeed Park, Devizes, Wilts. SNIO 3AN. investigation. From these seemingly simple recordings,

504 RADIO COMMUNICATION June 1978 the 29-502MHz signal. Fig 1(a) gives the tca as 2120gmt. at which time the satellite was at a distance of 3,074km at an altitude (elevation) of 16-7°. The Oscar series of satellites which have as their secondary purpose "the aim to have available a real satellite for direct student participation" are extremely useful in aiding teachers and/or lecturers to make satellite study a real and living study, and the issuing by AMSAT of the telemetry decoding calibration equations have

Frequency Shit enabled students to become intimately involved with the satellites' systems. The hf telemetry signal of Oscar 7, on 29.502MHz, is in cw mode and gives 24 channels of information each consisting of three numerals, the last two being the significant channel information. For example, from orbit number 2041 of Oscar 7. Channel 3A—battery voltage: significant figures (N) 72; calibration equation V= 0.1(N) + 6.4 volts, A student measuring doppler shift (suppressed-bea m thus 72 represents a battery voltage of 13-6V. method )

FrequenCy 51101 1.05kHZ the students base their initial predictions—sometimes with awe-inspiring success and at other times with baffling failure. This exercise certainly underlines a factor which some students initially overlook; that of the Earth's rotation! Students thus learn the need to produce accurate predictions if many hours are not to be wasted looking for a satellite which is not going to appear. and at this stage the students are introduced to the theory of satellite orbits. The apparent change in frequency, known as the doppler shift, is quite noticeable with radio satellites, and the students have made numerous measurements of this effect. To the ear the change in frequency heard in a loudspeaker is easily detectable, but one must bear in mind that the actual percentage change of the apparent Tinte fir, - a signal is very small, about ±0-0015 per cent. From the (a) lb) plot of the observed frequency against time, several Fig 2. Measurement of solar panel charging current determinations can be made; the two most notable being the time of closest approach (tca) and the actual distance between the ground station and the satellite at tca. From Figs 1(a) and 1(b) it can easily be seen that the frequency shift of the 145.972MHz signal is far greater than that for

a a

o o 2120 1833 one (GMT) T e (GM") (a) Cn:

Fig 1. Doppler shift plots for Oscar 7's tele metry beacons. (a) Orbit No 13570-145 M Hz. (b) Orbit No 13556 -29 Mhz

RADIO COMMUNICATION June 1978 size qt. the antenna. This would be true at one frequency if

I. the antenna could be resonated at that frequency without technical adding dissipation. It results from the fact that a smaller antenna delivers its lesser voltage from a lower resistance topics such that the available power remains the same." However. Wheeler also noted: "While the radiation pattern and, hence, the directive gain of a small antenna remain the same for a smaller size, the radiation resistance Pat Hawker, G3VA decreases relative to the other resistance in the coupling circuit. The resulting reduction in coupling efficiency is one of the principal limitations /the smaller antenna. Another HIS month the emphasis is on antennas, still the least aspect of the same limitation relates to the frequency Tunderstood and most mystifying part of an amateur bandwidth of operation with fixed values of the circuit station. Perhaps one day it will all be codified and become element. A smaller antenna with the same reactance and just a matter of selecting from the catalogues an radiation resistance must be more sharply tuned to deliver installation in which a graduated price scale determines its available power. Therefore, the reduction of size the results likely to be achieved: but that is very far from imposes a Jimdamcntal limitation on the bandwidth. If the the current situation! Antennas remain an area where bandwidth so limited is insufficient, further damping must novel ideas still continue to be developed, often at low be added at the expense of coupling inefficiency. cost; and where nobody. repeat nobody. can claim to "The limitations verify the experience that larger know it all already: or where this year's information is antennas arc generally more efficient, especially for likely to be rendered obsolete by next year's new wideband operation." components. Since the final test of an antenna is not made Since 1947 the development of the attire antenna has with a meter but by on-the-air operation. the antenna shown that for reception it is possible to match a short remains a direct encouragement to all three aspects of antenna effectively over a wide bandwidth, although this amateur radio: self-training, intercommunication and does not mean that a short active antenna erected inside a technical investigations. And the same ideas are often building (and thus close to sources of electrical in- directly applicable to hi. vhf and uhf operation. The terference) should be expected to provide the same signal- antenna. then, is a true microcosm of our hobby. to-noise ratios as an antenna out in the clear and having the benefit of height gain. Except at the very lowest powers. however, there has so far been little development Reducing the size of antennas of active antennas for amateur transmission. For many amateurs who are interested in operation at hi'. Two recent articles provide useful surveys of tech- or even 70M Hz. one of the perennial problems is the basic niques and characteristics of loaded short antennas: size of the dipole element. It would be so much easier in "Signal/noise performance of loaded wire antennas" by many locations if a 3-5MHz monopole (ie X/4 vertical in Dr P. A. Ramsdale (Proc IEE. Vol 124. No 10, October which the earth provides the missing half of the dipole) 1977. pp840-843) and "Properties of dielectrically loaded did not need a 66ft element, or if a I 4MHz dipole needed antennas" in the same journal (pp837-839). The former only about the same span as one for the 21M Hz band. covers a number of different forms of loading, including Over the years. of course, many antennas have been the trap loading commonly used by amateurs and less developed that provide the basic requirement of any well-known resistive and travelling-wave loading tech- effective antenna system (ie that it should represent a niques where the object is to obtain directivity with series-resonant circuit at the operating frequency) with relatively short antennas (though it is shown that these elements physically smaller than a standard X./2 dipole or should include at least a X/4 monopole section). This X/4 monopole. The use of loading coils, helically wound paper also brings out a point that has puzzled amateurs radiators, tuning and matching units. capacitance hats of for a number of years: the difficulty of getting a good various forms etc. are all tried and tested methods of vertical collinear array simply by using a succession of achieving series resonance: then there are such space resonant circuits (LC or stub) to provide 180° phase saving techniques as dropping down the high-voltage reversals. ends of dipoles or folding parts of the element in the form D. L. Smith (IEEE Trans Ant & Prop AP-23. 1975 of loading stubs etc, including those formed within quad pp20-27) studied such antennas and found that a 180° loops. More recently, there has been considerable work. phase shift was not achieved in this way but discovered particularly for military communications. on various that a collinear pattern was set up at a lower frequency forms of dielectric loading, including coating the element (about 0-8 times the design frequency). In the equivalent with a high-permittivity (ferrite) material. monopole case such an antenna will act as a 0-6X Some 30 years ago. Harold Wheeler wrote a paper inductive-loaded element with the load 0-2X. from the end; "Fundamental limitations of small antennas" (Proc IRE. its gain, however, is slightly less than an unloaded 1947. Vol 35, pp1479-84) which although concerned antenna of the same height. This could be the explanation specifically with receiving antennas still remains one of of the problem noted by G6CJ in making the coaxial the classic references on this subject. He wrote, for collinear antenna work (TT November. September 1972) instance: although I44M Hz versions of this antenna still turn up in "It has occasionally been pointed out that a small the amateur journals from time to time, and an app- antenna free of dissipation could take from a radio wave arently successful large hf array was described in IEEE and deliver to a load an amount of power independent of the Trans Ant & Prop July 1972. pp5I3-516.

506 RADIO COMMUNICATION June 1978 Doubly-fed coaxial antennas is the same as that along two monopoles connected in In Electronics Letters. 16 March 1978, Vol 14. No 6, parallel, since the current will fall to zero at the. midpoint pp178-9) F. Rahman and T. S. M. MacLean of the of BC. which has been assumed to be of negligible length. University of Birmingham describe a new form of dipole The input impedance in this case is that of these two X/8 antenna which, in its monopole form, is claimed to have monopoles connected in parallel, and is thus capacitive. useful height reduction properties and which it would To eliminate this reactance the length of the coaxial cable seem could also be developed as a vertically-polarized ABCD must be increased (it will be assumed without directive array of modest height. In monopole or dipole increasing the spacing 2d). When ABCD is made equal to form it provides a purely resistive feedpoint. ?f 3. for example. it can be shown that the antenna Two different forms have been investigated at Birming- behaves as a series rather than a parallel resonant circuit, ham with self-resonant heights (dipole) of X/3 and 1/4 and thus fulfils the requirement for any useful wire respectively (ie about X/6 and ),./8 monopole heights). The antenna. first type. it is stated, can also be made self-resonant at much lower heights and can then form a directive array. Basically these antennas are made by using doubly-fed. 160 40 air-cored coaxial line, folded back on itself so as to allow double feeding: see Figs I (a) and (b). 120 30 o 2c1 BO Resistive. 20 Theory it Experiment

E 40 e (H+d) (deg) 30 ij o re 15 • 75 ti 45 90 o o 100 200 300 400 Frequency (MHz) z-40 „'

—80 React ive. Theory Experiment —120

—160

Fig 2. Input impedance of the open-circuited doubly-fed (a) (b) coaxial dipole plotted against frequency. Based on model antenna at 300MHz with dimensions of 2H 14cm and 2d 7cm -.12. cot 2)5 (H+4) using 1.6cm diameter coaxial cable. The graph sho ws both resistive and reactive components of the input impedance, theoretical and measured. The reactive component, of course, is zero at resonance, leaving a purely resistive impedance of over 1 OSI

Fig 2 shows measurements made on a model antenna designed for 300MHz. Although the currents in the two monopoles are no longer equal. radiation patterns in both E and H planes were indistinguishable from those of a Fig 1. (a) The open-circuited form of doubly-fed coaxial conventional dipole, it is stated. Further experiments with monopole. (b) The short-circuited form that provides rather greater height reduction, even when the two branches are increasing separation between the vertical arms, but the closely spaced, but of rather narrower bandwidth. (c) Equiva- same height H. gave increased height reduction factors up lent circuit for the mathematically inclined to over 3 (spacing said to be 27cm) with radiation pattern then showing array type characteristics. Input resistance is approximately that of a single monopole of height H Operation of the antenna shown in Fig 1 (a) is when the spacing 2d is small, as indicated in Fig 2. The described roughly as follows: short-circuited form of this antenna, shown in Fig I (b), Let the spacing 2d be considered negligible initially, so appears to be rather less attractive as the bandwidth is that the electrical distance between e and the feed-points a reduced, although of lower self-resonant height. and e can be ignored. When the coaxial cable length Although shown in monopole form, the antenna could. ABCD is Jt./4, the input impedance between e and earth is of course. be used in dipole form. equal to the input impedance between the coaxial outer The experimental results would seem to be very conductor h and earth also. Hence equal voltages are promising and yet still, leave plenty of scope for further applied to the outer surfaces of both radiating arms. development and evaluation as an antenna for amateur Consequently the current distribution along AB and CD applications by anyone with some suitable spare cable.

RADIO COMMUNICATION June 1978 507 G6XN miniature and compact beams Antenna The February 1977 TT-included the powerful arguments SRecial coaxial cable of Les Moxon, G6XN. in favour of further development Coaxial cable SWR of effective, lightweight two-element minibeams capable Transmitter of about 4dB forward gain, achievable over restricted but _C) bridge practical bandwidths. One of the principal tools in achieving such results. G6XN then suggested. was the use Good of two open-wire feeders, one to each element, to allow earth fine tuning from within the shack and to permit just 180° rotation. The beam itself was loosely based on a form of Fig 4. All-band trapless vertical antenna, described by VE3FHS. in which the base impedance of the vertical element "neutralized" VK2ABQ. Now, in a letter written at the is transferred into the shack by means of a length of end of January. G6XN reports further on this project. He transmission line that is an exact multiple of an electrical writes: half-wave. The bese matching network can thus be adjusted "This development is going well, with dimensions (for from the operating position 14MHz) now reduced to 10ft square, using all-metal construction. Vertical rods, each 2ft long. support zig-zag shortwave club) in an article by Rick Murphy. VE3FHS. wire loading as roughly indicated in Fig 3. Two open-wire reprinted from The Canadian Amateur of unknown feeders are used and this is proving absolutely essential date: see Fig 4. because the operational bandwidth for a better-than- This idea provides a means of matching, within the 20dB front-to-back ratio is only 65kHz; for better-than- shack, the base impedance (which may be resistive or 10dB f:b ratio and less than 1dB drop in gain it is still only reactive) of a fixed-length vertical rod antenna, making it about I 30-200kHz. possible to use the element on different bands without any "Before putting this up in the air, in its new form, I have adjustment of matching networks located at the base of a few more measurements to make, including some the antenna. The resonant length of transmission line experiments with a view to eventual multi-banding. simply transfers the base impedance into the shack where Feasibility of this is already proved, but not the best it can be matched to the transmitter: for example, by a method." roller-coaster series-inductor or by other forms of transmatch. Accurate adjustment of this inductor is indicated by means of the swr meter placed between the inductor and the transmitter. The actual impedance of the resonant transmission line is of no consequence: VE3FHS suggests either 50 or 75n coaxial cable, although presumably the losses (due to high loft swr on this part of the line) would be reduced by using open-wire or 3000 line. The matching inductor is tuned Fig 3. Use of vertical rods to support zig-zag wire loading in for minimum swr at the usual operating frequency. and the latest version of G6XN's two-element 14MHz minibeam VE3FHS reports that bandwidth for an swr of under (see also 77 February 1977) about 1-7 is roughly 150k Hz on all bands. The system. it is stated, was tested with a 22ft vertical element working as 5118 on 28MHz. 1/2 on 21MHz, G6XN has also been working on anoiher form of extended ',./4 on 14MHz and as a base-loaded 44 on 7 compact VK2ABQ wire-loaded beam, improved by the and 3.5MHz. It is claimed to provide a better perfor- addition of a third element, with boom lengths of 1 1 ft, mance than is usually achieved with the shorter trap- 12ft and 13ft, element lengths of the order of 24ft. and vertical rod antennas. VE3FHS recommends the use ola with a performance "indistinguishable from that of big small loading coil at the base of the antenna to resonate it beams" over a restricted range of frequencies. This beam accurately at the highest frequency band (cg 28MHz), incorporates the "disappearing inductance" form of since this enables the shack tuning inductor to be smaller multi-banding and has already been pretty thoroughly and more easily tuned. with wider bandwidth at all tested at 14MHz; it has also proved itself on 28MHz, even frequencies. at low height. He used (for the cw ends of the bands) a 92ft length of unspecified coaxial cable (presumably having a velocity factor of the order of 0.7) to form an electrical k/2 at All-band trapless vertical 3-5MHz, X. at 7MHz, 2?.. at 14MHz. 3),. at 21 MHz and 4X On previous occasions attention has been drawn to an at 28MHz. To operate on 1-8MHz would require double important characteristic of any length of transmission the length of cable; for use only on 7MHz upwards, 46ft line that is one or more exact electrical half-wavelengths would suffice. Note that the feeder lengths will vary with long: the impedance at the far end of the line will be the velocity factor of the cable. The length is fairly critical precisely duplicated at the near end, whether or not there (within, say, I ft) and this can be checked by obtaining are pronounced standing waves along the line. This unity swr at the required frequency. If the lowest swr dip is property can be used, for example, as a means of tuning at a higher than required frequency. the cable needs quad or beam reflector elements from within the shack lengthening. VE3FHS found 92ft satisfactory for all (TT July 1973, ART, and also utilized in the G6XN twin bands, except 14MHz where he connects in an extra 2ft feeders). Another application of this appears in Zero Beat length. Clearly some experimentation may be required— (the lively monthly publication of the Victoria. BC. but then that is what amateur radio is all about.

508 RADIO COMMUNICATION June 1978 Franklin encore this should represent the only significant cause of As an addition to the earlier comments on Franklin frequency variation. oscillators (TT November 1977, April. May 1978). Harry In 1970 ZL2APC used two audio-type p-channel jfet Burton, ZL2APC, has brought to my attention two devices which had a limit of about 4MHz, but with references to solid-state oscillators of this type: the first, suitable polarity reversals n-channel fets such as the based on jfets, in an article he wrote for Break-in in MPF I 03. 2N3819 series could be used; today one would December 1970; and a short note by Carl Drumeller. also consider the use of dual-gate mosfets. The output is W5JJ, in Ham Radio January 1972. using bipolar taken from across a von resistor forming an un- transistors. bypassed portion of the source resistor of the second His own unit (Fig 5) was used as a transfer oscillator to amplifier. This is followed by a common-emitter npn track in on transmitted signals and helped him to win the bipolar transistor as a buffer stage driving a further p- NZART frequency measuring contests in 1969 and 1971. channel jfet. He considers that a source follower provides In his article he noted that the late Geoffrey Gouriett in better isolation than an emitter follower since bipolar his published description of the Gouriett-Clapp (or less transistors are not really unilateral; hence the use of the fairly the Clapp) oscillator in Wireless Engineer (April fet rather than a second bipolar transistor. 1950. p105) had commented that for maximum stability The 2pF coupling capacitors were made from copper of this form of series-tuned Colpitts it is essential to use tabs mounted on the frame of the tuning capacitor. some form of limiter to confine oscillation to a linear forming low-drift air-spaced and adjustable units. portion of the device characteristic. This is seldom found ZL2APC also noted that vernier-bandspread or remote in practice, except in a few diode-stabilized vfos. control could readily be incorporated as indicated, and a Harry Burton also noted that in the Colpitts, Clapp similar type of arrangement could also be used to turn it and Seiler oscillators the decoupling or isolation of the into a voltage-controlled oscillator for use with a huff- active device from the LC tank circuit is achieved by and-puff stabilizer or vco frequency-synthesizer swamping the capacitive changes caused by age or arrangement. temperature by the use of large shunt capacitances incorporated as part of the tuned circuit: the magnitude of these swamping capacitances is related to the mutual Using lamps, leds and neons conductance of the active device, and hence there tend to There are some components that have been around so be practical limits to such an approach, particularly with long that everybody takes them for granted. These lower gain devices such as jfets. The Franklin represents undoubtedly include miniature incandescent lamps, used an alternative approach. with isolation of the active for pilot and indicator lamps, dial lights, occasionally devices provided by the very loose capacitative coupling. even for matrix displays. Because they can usually be He listed the potential advantages of the Franklin as: replaced easily there is not much concern about achieving (1) No taps required in the tuned circuits, either inductive better reliability—yet most amateurs would agree that or capacitative. such miniature bulbs are among the least reliable of (2)The simple parallel tuned circuit has no extra capa- modern components. citors subject to ambient temperature changes and/or An article by Martin Grossman. "Focus on lamps" heating by circulating rf currents. (Electronic Design. 4, 15 February 1978, pp54-63) (3) It is capable of being used over a wide tuning range. includes much practical advice on how to keep such lamps (4)The two cascaded active devices used to achieve 360° burning—and conversely on what makes them fail. phase change can provide high gain even with low- How many of us, I wonder, realize that operating these gain jfets. lamps from dc greatly shortens their lives, compared with The basic tuned circuit is of course subject to the use of a low-impedance ac source? temperature/ageing variations, but in a well-made unit One reason is that dc is often fed to the lamp through a

10k 1 1 2k 1 -9V

z 680p TR4 2N4360 Fig 5. A 1970 Franklin solid- 1 270P state oscillator used very successfully by ZL2APC, including

1 - 9S the untuned buffer/isolator 12 e stages. It is sho wn in the op- 4.7k tional voltage controlled form

d — 2p 100k series resistor or through a semiconductor device. Unfor- 100k tunately the filament resistance of a lamp increases with s 2N4360 age, so that the voltage across any lamp forming part of a 84101 — I - -9V resistor chain will gradually increase. Even more deadly is the uneven evaporation of the filament (causing notches)

RA DIO CO M MU NICATIO N June 1978 509 60 70 80 90 100 110 120 130 140 A led always needs a series (ballast) resistor to limit 1000 current. A led can be operated from ac, but because the 1 500 \ , 300 reverse breakdown voltage is usually only about 3-6V. it • 200 • / 275 may need a series diode or diode in inverse parallel • • 250 É 100 / configuration, in addition to a series resistor. . • 50 •, 1.11e Candlepower 225 The light from a led tends to be more directional and

E 20 200 the user often needs to be almost directly in front of the • device (viewing angle often given as 28°) although some 10 '/14% ei t 17550 devices are constructed to have wider viewing angles (up 5 1 to about 65° or even 180° when used with special lenses). 2 Current 125 100 A cut-price led may well be a device with lower than rated 1 Cu rent 10 lx light output. since such devices are often weeded out 05 during manufacture and disposed of at bargain prices. dt 7 5 1 0 2J Like most semiconductor devices, a led can be Candlepower ..1.1te 0 I: V8 2 damaged by careless soldering; makers often specify a cl 1 o o maximum soldering temperature of 260°C for not more 1 , '''',1•., o.o than 5s. When attempting to fit a led into an 0. I in matrix 0 0 printed circuit board, note that not all devices have 80 70 /30 90 100 1 0 120 130 140 standard lead spacing. Percentage & DesIon Volts Miniature neons have a rated life a good deal better than incandescent lamps but only about one-tenth that of Fig 6. Typical life-expectancy curves for miniature incandes- a led. They last longer on ac than dc (about twice as long) cent bulbs and should not be exposed to high temperatures. An undesirable characteristic of some neons is a tendency to that. for reasons not fully understood, is more serious flicker due to movement of the corona discharge. with dc-operated lamps. It is suggested that ac operated lamps can last from 2 to 10 times as longas those operated Logical break-in from dc. An increasing number of hf cw operators appear to be Lamp life is affected, of course, by supply voltage. making effective use of fast, full "break-in" operation roughly in accordance with the type of life curves often (where incoming signals can be heard between letters and supplied by the manufacturers, as shown in Fig 6. It is, words). One hears stations using a quick "r" to eliminate however, important to appreciate that makers' life the need for the other operator to send twice the rst. QTH estimates etc are based on the devices being operated in or name, etc—a useful extension to the many other ideal rather than practical conditions. A lamp operating advantages of break-in in providing effective in a flashing mode will normally fail more rapidly. communication. although it has been shown that a flashing light attracts In Old Man, Nr 3. 1978, Emil Zellweger. HB9BAT, and considerably more attention than a steady light. There is Hans-Ulrich Boksberger. HB9ASX, describe a cmos logic also a danger of choosing a flashing time that excites system for "Full-BK (fast) without relays": Fig 7. Well mechanical resonances of the filament. High-voltage not entirely without relays since two high-voltage reed lamps have long, finely-coiled filaments with many relays (500V. 3A) are used for antenna changeover resonant points, and the adjacent turns may short circuit between transmitter and receiver, but the logic arrange- when a filament vibrates. Switching a lamp on and off' at ment is designed so that all operations, including keying, intervals sufficiently long for the filament to cool down receiver muting and antenna changeover occur in the will tend to reduce lamp life because of the high inrush right timing sequence. as shown in the timing diagram. current when the cold filament is first switched on. Fine adjustment of the timing is provided by RV!. Tungsten filaments, incidentally, are more fragile at room although for full details of the system reference may have temperature than at operating temperature. Ventilation, to be made to the original German text. usually by encouraging convection of air, keeps bulb temperatures low and will extend the life of the bulb. In comparison with an incandescent lamp, a light- High CI and a 4CX250B linear emitting diode (led), though normally providing less light During 1976 Bill Williams. G8AVX (25 Streetsbrook intensity, can last virtually for ever (a well-made led has a Road, Shirley, Solihull, West Midlands). described in half-life of over 20 years of continuous use!). In effect Radio Communication (October 1976) a useful 432M Hz useful life is determined by the gradual loss of light plate-line power amplifier, and a number of these have intensity and so tends to be measured to the point where been constructed successfully. However, one constructor the intensity has dropped to half its original value. But, of found that in AB2 mode the amplifier ran at high de input course, it is necessary to pay attention to a number of and produced much heat but very little rf. apparently due points if such longevity is to be achieved. to some form of parasitic oscillation. After correspon- Do not mix leds and lamps in close proximity: the heat dence, G8AVX undertook some bench tests of the from the bulbs can destroy the leds. At high ambient recalcitrant amplifier, but as a precaution inserted his temperatures the light output from a led decreases; well-worn 4CX250B instead of the brand-new American continuous running at 80°C or higher accelerates the loss one used by the constructor. The amplifier worked fine. of intensity. At low temperatures (which can crack the After considerable investigation G8AVX has come to bulb of a miniature lamp) a led can be extremely efficient. the conclusion that the pa stage is only conditionally

510 RADIO COMMUNICATION June 1978 PIT 105 TRa 18k

,e1ay

Key

Ground ,74 ICI to IC7 MCI4011 TRI BC107 TR 2 ..BC177 183 and 4 Vu >100V

0 Key In

1 0 Pu antenna Antenna 1 Ta antenna

P,. mutete o

0 ru key O - r tn.'s) IT 13 14 ti

Fig 7. Logic system for fast break-in operation showing timing sequence stable and, unless correctly neutralized, is inherently determined by the physical characteristics of the dia- liable to oscillation (tptg?) depending upon specific phragm material... today the best diaphragm is made of combinations of valve gain, inter-electrode capacitance thin polyester film which provides more accurate and tuned-circuit Q. Despite apparently effective "cold" vibrations than fluorocarbon film . . . however, because neutralization, it has proved steadfastly impossible to the electric charge on the surface of thin polyester film achieve entirely satisfactory neutralization of the higher- discharges rapidly, it could not be used until recently as a gain 4CX250B over all drive levels and with an anode diaphragm for electret microphones." (Sony advert for voltage exceeding I kV. their broadcast radio-microphone system based on a back G8AVX is slowly becoming convinced that this is likely electret condenser capsule). to apply generally to virtually any linear amplifiers using a Harry Burton, ZL2APC, suggests that the vhf align- full specification 4CX250B in high-Q cavities or coaxial ment aid described by J. R. Compton. G4COM. in the lines, although no problems are encountered when the January 1976 issue of Radio Communication (and see also stage is operated Class C. He is therefore wondering if any alternative noise source by LA8AK in TT. February other readers have encountered and beaten this problem 1978) is worthy of further publicity. He writes: "It is without resorting to such brutal measures as a passive extremely useful, relatively simple and easy to get going. I grid arrangement with resultant lower power gain. If not. modified mine of course (what else!) to use a higher it looks as though one amateur will have to convert to the output noise source (BC107 as a zener) with a switched use of a grounded-grid triode. attenuator between the noise source and the output terminal (I0dB per step). TR3. 4 and 5 arc run at full rail En passant voltage and RV3 is an internal adjustment to make sure Polystyrene containers represent a fire hazard. The the BC107 zeners. polystyrene is inflammable and not sell-extinguishing and "It may be of interest that, of all the transistors I tried. will burn with an orange-yellow flame, developing a about the noisiest as a zener was the BC109! The device is dense, black, acrid smoke . . . fire extinguishing devices very useful on 70cm. and most of the local vhf/uhf gang and prohibition of smoking in areas with such containers are enthusiastic. Hewlett Packard seem to make a is recommended (ABU Technical Review. March 1978). comparable unit (HP Journal February/March 1959 and "Research and critical listening tests have indicated January 1958) and this still appears in their catalogue as that the tone quality of a microphone is ultimately the 340B." El

RADIO COMMUNICATION June 1978 511 controlled by WB8ZJW and HI8GMC, and some of the stations taking part one evening recently included the month HKOQA, HC8G1, KH6JEB, KL7IYH and C5AAP. There is now a resident amateur in Tuvalu whose callsign is VR80. He has been noted around I 4,205kHz on the air after 0900. A35N W is a new Tonga call which is held by a New Zealand amateur who will be in the islands for another five months or so. • John Al'away, G3FKM * Peter Reed, G4BVH, returned to Masirah Is on 8 May. He will be there for about three months and hopes to be using his previous A4XVK callsign—mostly on cw—on Fr HE writing of this month's MOTA has been con- all bands 7 to 28MHz. Peter will use dipole antennas. siderably hindered by the writer's absence during a ZD9GG has now closed down, and it seems that there visit to the IARU Region I Conference in Hungary. Full is no amateur with the new group of meteorologists on details of the proceedings will appear at a later date, but Marion Is, so that the island will not be heard for a while. suffice it to say that no change in band plans, or in any The prefix for stations situated in the Yukon Territory other matters affecting those who use the bands below was changed from VE8 to VY 1 on 25 April. Northwest 30MHz, were made. Representatives of over 30 Region I Territories stations will continue to use VE8. societies were present, and the event once again em- YI I BGD has been appearing regularly on or near phasized the vast fund of goodwill and friendship which 14,230kHz and attracting great attention. Unfortunately exists among radio amateurs of all countries— signals are rather weak and it is hoped that better irrespective of national politics. equipment will soon be available. G4BPX is the recipient of a large number of cards for VR3AH should now be back on Christmas Is, and his "GU4BPX"—mostly from the USA, and apologizes to new QSL manager will be WB4PRU. Some logs for those who have contacted the pirate as he cannot confirm Doug's previous operation from the island (when K2BT their QS0s. was his QSL manager) have been lost. Stations in the 144MHz fm. G4BPX is the recipient of a large number of Solomon Is are due to start using the H4 prefix in July. cards for "GU4BPX"—mostly from the USA, and Maurice Caplan, VS5MC, is believed to have left apologizes to those who have contacted the pirate as he Brunei and returned to the UK. cannot confirm their QS0s.

Top band DX news In spite of the lateness in the year, G3C WI reports contacts with W I ZM (ssb), K2ANR, W8LRL and 0E5XH M is the callsign of a special station located in VE1BCZ, around 0400. He would like to publicise the Hochburg. Austria, and celebrates the city's 1,100th current popularity of the band in the Midlands for mobile anniversary. The activity will continue throughout the use—especially around I,910kHz. year and special QSLs will be sent out. Fred Laun, K3ZO, who has previously operated from LU, HS and HI, was due to arrive in Thailand at the end of May. He will be there for three or four years and hopes Dxpeditions to get the callsign HSI ABD. When he gets on the air he It is now known that 4Z4TT will be in Niue during the will mostly be on 3-5, 7 and 28MHz, and QSLs for him period 26 May to 9June. He will have two Atlas 210s, plus will be dealt with by K3EST (5801 Huntland Rd, Temple external vfo, a TH2-Mk3 beam, and dipole antennas for Hills. Md, 20031, USA). 3.5 and 7M Hz. Operating frequencies are listed as: 3,795, BRS33915 has pointed out that WBOMSZ produces a 3,895, 7.085, 7,155, 14,195, 14,280, 21,245, 21,355, 28,495 very useful QSL manager directory—it consists of a print- and 28,600kHz. The expedition will only use ssb. QSLs out which is up-dated weekly from information received should be sent direct to Baruch at the address in "QTH from all over the world. It costs $1 and may be obtained Corner", and requests should be accompanied by $1 and direct from Gary Yarus, 921 N Clay Ave, Kirkwood. Mo, sae—please do not send ircs (this requirement, if meant to 63122, USA. apply to stations outside the USA, appears to be ZL4LR/A, on Campbell Is, has been advising contacts unfortunate). to QSL to ZL3FE—his home callsign. However, as he will Jim Smith, P29JS, will be on Cocos Keeling Is from 30 be on the island for about six months, an arrangement has May to 14 June as VK9YS, and will use now been made whereby a faster QSL service may be 14,005-14,010kHz on cw, and 14,195, 21,255 and obtained via N4NX (see "QTH Corner"). VK2AGT, 28,600kHz on ssb. QSLs should be sent via K4UTE. Lord Howe Is, is reported to be found occasionally on 3B8DA hopes to visit St Brandon and Rodrigues Is 14,218kHz after 1330. Permission was given to stations in during the year. This may mean that he will be 3B7DA or New Zealand to use the whole arca 7 to 7.3MHz from 19 3B9DA during June or July. At present he has trouble March. with his transceiver. GW3CDP reports a dx net which meets at 1700 each The final QS0 count for the FOOX expedition was Monday, Wednesday and Friday on 21,275k Hz. It is 29,069! Of these, 21,000 were with N America and 4,000 with Europe; about 800 of the latter were with France. The QS0 rate was 187 an hour—a very creditable •10 Knightlow Road, Birmingham BI 7 8QB. performance. The departure from Clipperton was rather

512 RADIO COMMUNICATION June 1978 dramatic duc to rising seas—but reports say that all the equipment was saved, although no attempt was made to remove the antenna towers as there would have been no chance of getting them onto the ship. In the course of moving the equipment, HB9A HL received a head injury. Fortunately the details of 29,069 contacts in the logbooks were safely preserved, and QSLs are expected from the printers early this month. HC5EE, who operated from Galapagos Is as HD8EE last year, expects to return to the islands this summer— possibly in June. Jack Leib. HB9TL, will be in Corsica and using his FOCH/FC call from 16 July to 3 August. On cw he will transmit 19kHz above band edges. and on ssb he will be found on 3,778, 7,091. 14,193. 14,275, 21,275 and Eric Rogers, 9H4G (Formerly G3H GX), has been living in Gozo 28,493kHz. QSLs go to the address in "QTH Corner". for seven years There are rumours of possible activity from the Neutral Zone during June. It may last for two weeks and the operators are likely to be JY3ZH, JY5HH. 0E6EEG, 9K2DJ and DJ9ZB. Danish expedition to OY during the period 28 June to 26 July have been received, and as this group intends to News from overseas operate on 144, 432 and 1,296MHz. activities from OY G2HJT has kindly provided a list of amateurs in the VP8 will be mostly confined to the hf and If bands. area which was sent to him by Vic Redsull, VP8PP, who Hull University Radio Society is making a trip to Eire left the Falklands on 10 April. The list of licence holders for 10 days during July. Activity will be on all bands IS to on 23 March was as follows: VP8AH (Salvador), VP8A1 28MHz, cw and ssb, and those looking for a contact on (Roy Cove), VP8BN, DQ and DR (Stanley), VP8GN 1.8MHz should listen on 1,820 or I,825kHz. Trans- (Port San Carlos), VP8HY (Stanley), VP8HZ, JB (Saun- missions on other bands will be centred around 14,210, ders Is), VP8JC, JE (Stanley), VP8ML (Teal Inlet), 21,290 and 28,590kHz. QSLs should be sent via G4FVP VP8MV (Goose Green), VP8MZ (S Sandwich Is), (C. L. Davies, 210 Whitehall Rd, Bensham. Gateshead, VP8NE (Goose Green). VP8NJ (Stanley). VP8NL (San Tyne & Wear NE8 4PU) direct or via the bureau. Carlos), VP8NO (Stanley), VP8NV (Goose Green), VP8KR (QTH unknown), VP8NY (Teal Inlet), VP8NX 10m OR P (Saunders Is), VP8OD (Stanley), VP8OH (Port Howard), On 5 January this year, G8LZH, using the station VP8OK (Goose Green). VP8ON, VP8PA (Port Howard), belonging to his father, G4EBZ, worked 14 USA stations VP8PC (Stanley), VP8PE (Hill Cove), VP8PH (North with the power from the low output socket of an FT200— Arm). VP8PK (Hill Cove), VP8PL (S Georgia). VP8P0 around ¡W, and possibly less. Earlier the same day over (Port Howard), VP8PR (Port San Carlos), VP8PS, 200Ws had been worked using full power (there was a VP8PT (Stanley), VP8PU (Chartres), VP8PW, VP8PX contest taking place) and the first QRP call was not and VP8PY (New Is), VP8QB (Salvador). VP8QC. intended to be serious until the usual 5 x 9 contest reports VP8QD and VP8QE (Stanley), VP8QF (Rothera Base, came back! The exercise was repeated on 25 March Antarctica), VP8QG (Chartres), VP8QJ (Fox Bay East). during the WPX Contest, and all USA districts apart and VP8QI (Faraday Is, Antarctica). It is interesting to from W6 and W7 were contacted between 1500 and 1550. note that the callsign VP8MZ is issued to the British W6s and W7s were heard at good signal strength, but it is Antarctic Survey for use in the S Sandwich Is. thought that the G4EBZ signal was lost in the QRM from the other USA stations. The antenna in use was a home- Expeditions made three-element Yagi, at 60ft and 20ft above ground Full details of the visit by GM3OLK, GM3YOR. respectively on the two occasions. G4DXC, G4DSE, GM 8NCM, and possibly G8HDR, to Iceland and the Faeroe Is during the summer have now Contests been released. The group will be in OY from 18 to 2I.July, The All Asia Contests and in TF from 23 July to 5 August. Callsigns will be as 1000 17 June to 1600 18 June (cw). follows: (cw) GM3YOR/OY and GM3YOR/TF, (ssb) 1000 26 August to 1600 27 August (phone). G4DXC/OY and G4DXC/TF, and (vhf) GM8NCM/OY This contest is between Asia and the rest of the world and and GM8NCM/TF. Frequencies to be used are listed as there are single-operator, single- and multi-band, and follows: (cw) 3,512, 7,012, 14,012, 21,012, 28,012. 144,012 multi-operator (single-transmitter) all-band categories. and 423,012kHz; (ssb) 3,736, 7,072, 14,236, 21,272. Exchanges consist of RS/T plus a two-figure number 28,536. 144,236 and 423,236kHz. Should permission be indicating the operator's age (ladies send "OO"!). obtained for operation on I.8 or 70MHz, frequencies will Each contact counts one point, and the multiplier is the be 1,836 and 70,072kHz (cw) and 1.912 and 70,236kHz total of different Asian prefixes worked on each band (ssb). No schedules are being accepted, except for meteor added together. Note that KA stations do not count. scatter operations, and Alistair, GM8NCM, is working Logs should indicate new prefixes worked, and separate on a programme to incorporate all requests. Meteor sheets should be used for each band. A summary sheet scatter operation will be on 144.175MHz. As details ola showing the scoring and other information, and signed

RADIO COMMUNICATION June 1978 513 GTH CORNER 2285, Caracas 101, Venezuela. A remittance of $2 or its A351-10 via VE3EDG. D. R. S. Bush. 105 Shipley St, Thunder Bay. equivalent in ircs is requested from those applying for a Ont. Canada. A3511/18 via DF2RG. G. Jaeger, Ruhseugstr 6A, 8460 Schwandod. certificate. In the 1977 contest (cw section) G3ESF won a W Germany. plaque as top entry in the single-operator all-band class. A35N W via K8NM, D. E. Heil, 5075 Shepherd Rd. Cincinnati. Ohio, 45223, USA. A4XFE Steve Christmas, PO Box 8530. Sala lah. Sultanate of Oman. The IARU Radiosport Championship A7XZZ W. Hurter, PO Box 3735. Doha, Qatar. 0000 8 July to 2400 9 July. FOCH/FC J. Leib, Eingangstr 39. CH-8580 Amiiswil. Switzerland. A maximum of 36 hours only for single-operator H5AA Private Bag 2001, Montshiwa, Bophuthatswana, S Africa. HABIARU via HA9K0B, Radio Club. Rakoczi Utca 12. 3530 Miskolc. entrants. There are single- and multi-operator single. Hungary. H H2CG PO Box 428. Port-au • Prince. Haiti. transmitter categories. The contest covers 1.8 to 28MHz, HH2CL PO Box 501. Port-au- Prince. Haiti. and the same station may be worked one per band HH2SD via VE3CVZ, F. E. Wallace. 11 Windham Dr, Willowdele, regardless of mode. Contacts via Oscar count as for a Ong, M2K 1X7, Canada. HKOBDG Box 842. San Andres Is. Colombia. separate band. QS0s with own country count one point, KM6FC now via K50A. R. .1. Guidry. RFD 1-Box 63 -CR, St Amant. La, 70774. USA. with other countries in same continent three points, and W6OKJ/KS6 Box 2609. Pago Pago. American Samoa, 96799. with all others five points. The multiplier is the number of G M3WBZ/LX via GM3WBZ. D. H. Facer, 21 Don St. Grangemouth. diffèrent [TU zones contacted on each band added Stirlingshire, FK3 8HD. K4SOT/SU 2424 Riviera Drive, Vienna, Va, 22180, USA. together. Exchanges consist.of RS/T plus ITU zone (UK VK9YS via K4UTE. W. R. Hicks, 8201 Cassie Rd. Jacksonville. Fla, 32221, USA. is 27). All entries should be sent to IARU HQ, Box AAA, ZK2AT via 5W1AT (see below). Newington, Conn, 06111, USA, from where contest ZL4LR/A W T. Barr, 305 Alpine Drive, Roswell, Ga, 30075. USA. forms may be obtained. A supply may be available from L4CU./A via ZL4AV. L C. Pickford, Talepa Rd. Otatara, RD 9, Invercargill. New Zealand. G3FKM but had not arrived at the time of writing. 4Z4TT Baruch Scheinberg, Box 22572. Tel-Aviv, Israel. 5W1AT M Maessen. Box 1069, Apia, Western Samoa. In the 1977 SP DX Contest top UK entrants were (ssb 9G1JX via 0 L7SI, Ralf Siegel. Backnangerstr 11. 1000 Berlin 28. W Germany. section) G4CVZ— 10,353. G4EJA -3,360, and 9M6V W Labuan Signals Regt, Labuan Is, Sabah. Malaysia. G3IRM/M -720 points. On 14MHz G3VOF scored 5,400. GW3SLA 4,824, and G4ETK 2,142 points. In the RSGB OSL Bureau. G3DRN, 30 Bodnant Gardens, cw section G3ESF scored 21,816, and GW4FCG 3,300 London SW20 QUO points, and on 14MHz G6NK 1,488. In the listener category BRS3593I (who kindly provided this infor- declaration that rules and regulations have been observ- mation) earned a certificate with 2,700 points in the ssb ed, should also be enclosed. Logs must reach JARL section. Contest Committee. PO Box 377. Tokyo Central. Japan, no later than 30 September. Results will be sent to those A wards including an irc and sae. Worked All Brazil For confirmed contact with all 22 Brazilian states and the I I th World Festival of Havana Distrito Federal. A special ribbon will be added if all four 0000 3 June to 2400 4 June: same times 10 and 11 June. territories have been confirmed as well (these are Celebrates the I 1th World Festival of Youth. Both Amapa—PU8. Fernando de Noronha-PYO, Rondonia— sections are phone and cw, and exchanges consist of RS/T PW8, and Roraima—PV8). Minimum reports of read- plus serial QSO number. Likely QRGs to find Cuban ability 3 and tone 5 will be accepted on QSLs. A list of stations will be 3.530, 7.030, 7,080, 14.030, 14,180, 21,030. QSLs, certified by a national society awards manager or 21.230, 28.030 and 28,600kHz. Note that the special two licensed amateurs, should be sent (accompanied by prefixes CL2, CL6, CL8 etc will be in use for the first time. 10 ircs) to: LABRE Headquarters, Awards Manager. PO Box 07/0004 Brasilia, DF, Brazil, CEP:70000. The Venezuelan Contest 0000 1 July to 2400 2 July (cw). W elcome 0000 29 July to 2400 30 July (phone). Apologies for the omission of this paragraph from the last This is a world-wide contest and all countries may be few months' MOTA. It is hoped that such a break will not worked. It covers all bands 3.5 to 28MHz and has single- occur again. Those who joined the Society during March operator single- and multi-band, and multi-operator included: CT1RQ, DCOMT, DC5CZ, DF4NU, El3CT, single- and multi-transmitter sections. Exchanges consist Fl OK, F6DLA, HR3JJR, JI1QFF, ON6UG, SM7CEH, of RS/T plus serial QSO number (from 001). QS0s VE3EMU, VE6CIY, VP2LCT and ZS6HV. between stations in diffèrent countries count two points— with one's own country contacts may only be made for Band reports multiplier credit. The multiplier is one for each DXCC The past month has been marked by several very country, YV call district. and USA call area worked on disturbed periods—the one around 1 May causing each band. Final score is total QSO points multiplied by complete disruption of the hf bands. According to the the sum of the multipliers worked on each band. West Coast DX Bulletin, Zurich smoothed sunspot figures Certificates will be given to those who contact (1) 10 YVs for the months ahead are June (62), July (65), August (69), plus 10 different countries, or (2) to listeners who report and September (73). Conditions on 14MHz have been hearing 50 complete contacts, including at least 10 YVs patchy, but with some periods of very strong signals from (both exchanges must be listed). The usual signed ZL. 21M Hz has been disappointing, and 28MHz rather declaration and summary sheet should be included with erratic—but good at times into the Far East. the log, which should be posted before 15 September (cw Thanks are expressed to the following for supplying the section) or 15 October (phone section) to: RCV, PO Box information used in compiling this section: G2HKU,

514 RADIO COMMUNICATION June 1978 G5JL. G3KSH. GM3LYY. G3RCA, G4EHQ, G4ETN, BRSs 17507. 31301. 33915 and 38280. Propagation predictions Stations listed in italics were using cw-the rest ssb.

3 5 M Hz, 0000 EA8 C Q. 4X4 H Q. 9G1 J X. 01 00 J3 A A G. 03 00 VP 9IR. Su m mer conditions will continue throug hout Ju ne and into July and Y V5 A K. 05 00 VP2 LD B. 070 0 VP 2 LLF. 23 0 0 0E5 C A/Y K. A ugust. This means continuing poor dx con ditions on the ht bands, 14 M Hz. 06 00 FO B DT. 07 00 CE O AE. KC 4 U S V, KG6JAR, V K9 NI, especially 28M Hz. O n this band eve n Africa and South A merica will V R 3 A K. ZL4L R/ A, 5 W1 A X. 08 00 H C 8 G1, KH 6. KL7. K M 6F C. VR8 0. not be heard with any certainty, but only on deys with above average YI1 B G D. 09 00 JT1 K A A. KOAXIDUZ K C 6 C V. W 6 0 KJ/ K S 6. VR 4s BF. m ufs. N orth A merica and Japa n will only be heard under exce ptio nal DJ. 1100 3 D 2 U P. 13 00 W D 8 O UZ/ K H 2 (Gua m). 14 00 circu mstances. 21 M Hz will also be influenced by poor su m mertime W A4 Y V G/ V Q 9 (O SL to K4 G L A), YI1 B G D. 1500 JT1 B K. P29..15, conditio ns. North A merica. Australia and Japan will only be heard on 9 M 6 V W, 9N1 M M 16 00 FB 8Z M. 7 07 L W (7 genuine). 1700 EA9F L days with above average m ufs. W estern N orth A merica. Japan and (Box 354, M elilla). FB 8 X S, KG 6JIU 1800 F R7 B V (BP 75, St Louis). A ustralia will be heard via the indirect path at the times indicated on the KX 6 B U, V S5 X U 19 00 H M 2J N, JT1 A N. VE1 A CJ/ S U (QS L to chart. Stations in southern Euro pe will find con ditions slig htly better VE1 AIZ). V S 6s CZ. H G. 2000 A 4 X G B (Q SL to G 4 C TIO), FY7YE, tha n those in the north. A s mall co mpe nsation for the poor dx W A3 W A Q/T.J. T R 8 N WL. Z D 7 M G. 2100 SU1441, T R 8 A C 2 (Q S L to conditions will be sporadic short skip on 28 and 21 M Hz over distances W B4 R Z N). VP1 B B. 22 00 HH 2s SO, V. 9K2E W. 230 0 ZL 4L Z, 9 M 2 P V. of abo ut 50 0 to 2.00 0k m. 21 M Hz. 0800 HM2JN. 09 00 A35MB. J A, U AO, ZL, 5 W1 8 K. 10 00 KL7IX Z, VE1 A SJ/ S U 11 0 0 J A, P2 9J S. 13 00 H K O B K W. 14 00 W hile the F2 m ufs fall considerably during the dayti me in su m mer W A6 O X Z/V Q 9, W 65. 16 00 HS1 W R. KC4 A A C, 5H 3F W 17 00 S79 M C, conditions, at nig ht they are m uch higher than in winter, so that 0 E 5 C A/Y K. 18 0 0 A 4 X G Y (QS L to K2 R U). C 5 A 8 K/ A, P29J S. 14MHz will offer goo d dx durin g night time: being open during the W A4 Y V G/ V Q 9, W 6s, W 7s. 1900 A2 C M D, H H2 S D, HZ1 HZ, KL7IV O, latter half of the night to North and South A merica. The best conditio ns Z D 9 G G. 5H 3 K S. 200 0 C21 A A. H K O CLA. S7 9 D. 21 00 W 7 Z G A/K G 6. for South Africa will be bet ween 190 0 and 230 0g mt. 220 0 LU, PY. ZP. 29 M Hz. 08 00 JA. VK6. VS6CZ 09 00 CT2, J28 A G, JA, U L7. 1000 D X conditions on 7 and 3'5M Hz will be relatively poor during the EA 9F C. JA, VE1 AJ L/ S U. 11 00 AP2 P. TR 8 G D C. VK6. 12 0 0 J2 8 A M. night as the nights are short and static is greater on these ban ds during P29 N K V. 1/K8. Z D8 R G 130 0 CE3IT. J2 CIA. V U. YK, 8P6 C G. 1400 su m mer nig hts. 3.5 M Hz will not be interru pted by the dea d zone in the JY 5 A R. 3B 8 C V. 150 0 VP 8 P M. 3D 6 B E. 5H 3 B P. 5V7 A H. 16 00 A2 C Z V, early hours of the m orning. O K 2 B F P/ D 2 A. XE1 J, 515. 7P 8. 1700 JA. V P8 N X, Q C. 0 E 6 D K/Y K. 9 M 2 D W. 180 0 KV4, LU. P Y. V U 2 K T. ZS. 19 00 CE. LU, PY, ZD8, Z P. The provisional sunsp ot nu m ber for M arch 197 8 fro m the S wiss 200 0 H C. H H8 A O. HI, W 1 - W4. Federal O bservatory was 73 .5 with a consistently high daily nu mber Many thanks to those who wrote in with news items. throu g h out the month. On 4 March the nu m ber exceeded 100, the first and also to the authors of the following: the West Coast time for m any m onths. The predicted s m o othe d nu mbers for July. DX Bulletin (WA6AUD), DX'press (PAOTO). CQ A ug ust and Septe m ber are 65. 69 and 73 respectively. Magazine (W I WY), the E.v-G Radio Club Magazine (W3HQ0). DX News Sheet (Geoff Watts). and Long Skip 14 M Hz JU N E 197 8

(VEIAL/3). US A- East W1 - 4 5 .11 . 3 7, W ( r 'A• I . Please send all items for August issue to reach G3FK M USA - West W 6,7 S = Il o o ¡ ¡ C o i no later than 28 June. and l'or September by II August. Caribbeen 6Y5, F M, T I S I MI MI MIN EZ O ¡ o o = MI Please note the very early deadline for the August issue. Brazil PY S M I MI M M Z : ¡ C E =Z M

South Africa IS 5 21 : ¡ C M : ¡ E Z Z2Z BI MI M o S E Asia H S,9 M2 S Z Ej ¡ i C reZIZ M Z . M .11 S ' ' o i : g l2 = Zete = Australia VK o o L : CtS MIZ a o o HF propagation study o Japan JA S : : o 11= = = = = 1 1 . 1 1

Preulletecl hpls (MHz • 10) lof June 1978 Tim e (G MT) 00 02 04 08 08 10 12 14 16 18 20 22 24

GMT 00 02 04 06 08 10 12 14 16 18 20 22 24 Aden 219 208 242 286 288 290 290 290 308 313 268 225 219 21 M Hz JU N E 197 8 Ascenuon 169 184 164 174 290 294 299 301 307 336 298 229 169 o 211 199 242 274 276 277 275 274 291 313 266 273 211 U S A- East W1 - 4 S Z a ; o i o lev, ,oevr mo 239 239 255 260 244 215 197 Beligkers 197 197 227 242 248 246 o Illadbeclos 241 211 176 181 204 251 249 253 255 266 286 289 241 ¡ bermuda 234 196 167 161 183 219 234 234 237 241 253 270 234 U S A- West W 6,7 o o i o 809014 241 209 173 177 214 228 247 243 249 260 275 282 241 L P et =11 o o Buenos Aew 216 214 191 164 133 196 280 280 280 299 324 296 216 Cape Town 164 114 105 205 298 303 304 307 319 296 220 205 164 Caribbean 6Y5,F M,T1 S Z a ¡ 1 YeZA V. W4 Colombo 195 199 241 266 770 270 767 762 282 249 229 200 195 268 Brazil PY 64 CHaeus 196 186 220 249 /48 258 253 251 288 205 229 196 s 1112222 = .I Oak., 239 220 210 232 290 294 299 301 307 336 338 275 239 I . m iume/.. Denver 202 171 164 145 141 155 177 196 206 200 209 221 202 South Africa ZS 5 : 1 „I II Forbanks 181 171 171 181 181 190 187 187 183 183 183 183 181 c-v., FelHarun 149 134 121 119 112 172 286 286 288 310 310 209 149 SE Asea H S,9 M 2 S : , . - Obrahe, 153 138 129 166 185 181 180 181 181 199 204 180 153 I I $'A Hong Kong 192 196 215 223 233 233 229 227 238 230 220 213 192 S 1 toé i l ¡ 1 i Honolulu 191 16$ 166 171 183 196 192 177 200 202 202 196 181 Australie VK i t 1 i Icetans1 105 100 101 120 154 172 182 180 185 178 183 130 105 L ¡ ¡ . , : 0203 dameras 233 196 187 172 176 221 7371 733 238 244 257 274 233 351 305 252 225 Japan J A S : : l , : 1-4904 225 218 199 263 295 298 303 307 318 Lat Palmas 220 199 171 210 255 256 243 252 255 285 294 266 220 Lena 242 202 181 188 201 173 261 261 281 274 298 293 242 Tim e (G M T) 0 0 02 04 05 OB 10 12 14 15 18 20 22 24 Los Angeles 196 168 164 154 145 141 174 196 202 200 213 219 196 Malte 172 161 162 201 216 215 211 213 216 238 235 206 172 Maur«. 176 145 730 288 288 294 294 298 317 332 291 227 176 28 M Hz JU N E 1978 Mener, 221 183 164 187 171 164 213 215 225 228 237 244 221 Moxoyr 102 158 181 188 202 202 197 195 195 218 216 195 162 I 1 U S A- East W1- 4 5 Noroth 171 176 720 289 293 294 298 301 315 284 219 2002 19 21,7)01 i 1 I Il 1 r. 1- ,1 New >Un 200 197 233 249 256 256 249 246 265 268 238 • i Caribbean 6Y5,F M,T1 S : New York 221 188 162 147 155 194 209 211 216 223 223 o i . Osaka 187 186 197 202 708 210 214 209 216 214 213 Brazil PY S ¡ Peuh 202 197 239 205 268 267 256 233 181 174 154 221.'13°9 21'0822'1 : l 1 . V • RIO De damera. 246 224 710 177 us 281 286 286 288 309 327 290 246 South Africa 25 $ I Sehsbury 229 192 178 289 295 301 304 310 321 352 299 260 229 I I isa 160 238 288 289 291 293 294 313 232 188 194 189 Seychelles SE Asie H S, 9642 S ¡ ! ; 1 ! ¡ 5Agapore 200 197 233 249 256 256 249 246 252 241 219 187 200 178 171 181 les 194 196 196 200 176 201 196 187 178 i 1 Suva (H Australla V K s : Suva II) 243 224 199 255 205 183 164 164 158 155 290 275 243 : 4 : 1 , Srghey 192 196 216 223 233 233 209 177 189 168 152 213 192 Sofney 0/ 242 218 183 192 210 152 139 136 133 120 177 294 242 Ti me (G M T) 00 02 04 06 08 10 12 14 16 18 20 22 24 telseran 204 199 241 266 270 270 267 262 282 303 263 230 204 Vmcouyo 183 164 164 171 177 174 183 187 190 202 202 200 183 Wellington Is) 187 183 187 196 206 206 186 Si 149 155 206 194 187 Short path 1 =11- 5 days = 6-2 0clays Wellington Il/ 748 224 201 191 152 139 133 129 126 114 218 285 248 Long path Bangs mcanmended *gel hose ha harem Spi ana full Opt O penings on more than 20 days in the m onth

RADIO COMMUNICATION June 1978 515 Wave Magazine, yet despite this blanket coverage, no one has written in to support the proposer's idea. 4-2-70 The most interesting letter came from Ray Wells. G3RIN. of the Philips Laboratories at Croydon. App- arently Philips have been working on a single sideband LGraham Knight, GM8FFX system for commercial users for some time. In fact Mr Wells is to present a paper on the Philips system at the July Radio Receivers and Associated Systems Conference Moonbounce at Southampton. This event is being organized in Many stations were active during the April half of the conjunction with the RSGB (see "QTC" last month). ARRL sponsored International Earth-Moon-Earth Taking into account the fact that commercial compan- Competition with high European activity on both the 144 ies have already done a great deal of work in designing and 432M Hz bands. Peter Blair. G3LTF, at Chelmsford, and developing a working mobile ssb repeater system. worked the following stations on 432M Hz: F2TU, F9FT, and the views expressed by the membership, the VHF I5MSH, K2UYH, K3NSS, K5.1L, SM2AID, SM5BFK Committee has decided to reject the GB3SF proposals. and, best of all. JA6CZD in Japan. Peter also heard LX I DB, W6ABN, KH61HP in Hawaii and XE1RY in SideWinders On Two- SWOT Mexico. All Peter's contacts were on cw, with the Ken Martin, W5ARR. of Fort Worth. Texas. recently exception of K3NSS who was also worked on ssb. K3NSS paid a visit to RSGB headquarters and left behind a large uses an 80ft dish antenna and was the strongest signal pile of information sheets about SWOT. an association received by G3LTF during the 48 hours of the contest. made up entirely of sideband and cw operators. The Dave Price, GW4CQT. at Cwmbran in South Wales, purpose of the group is to promote the use of ssb and received his special high power licence in time for the other modes, with the exception of fm and repeaters. contest, enabling him to have a 20min moonbounce QS0 During a recent contact with GM8FFX. Ken Martin with SM7BAE on I 44MHz. GW4CQT heard, but did not described how it was decided to form a group to help work, KIWHS, DK1NGA, 14EAT, W6P0 and W7FN protect the dx sectors of the 144MHz band from being on 144MHz, and K3NSS on 432MHz. RSGB vhf taken over by "closed" repeaters. Since the FCC manager. Ian White, G3SEK, rushed home to Didcot deregulated the rules governing repeaters in the USA. from a committee meeting at headquarters in time to many "private" repeaters have started up on frequencies work K1WHS on I44MHz. formerly used by stations chasing dx on ssb and cw. Many stations listened during the contest, and Douglas SWOT was formed in March 1976 and now has 1,200 Parker, G4DZU, at Leeds, using a 56-element array, members, most of whom operate around the dx calling heard SM7BAE, K I WHS and W7FN on 144MHz eme. frequency of 145.100MHz. The group publishes a Peter Bacon, G3ZSS, led a team of licensed listeners who monthly bulletin with dx operating news and articles on put up a 400ft per leg rhombic antenna especially for the Es and auroral propagation. They also gave publicity to event. Several stations were heard on 144MHz on a Yaesu the RSGB VHF/UHF Manual, quoting from it in a FT22 I. and it is hoped that their friendly farmer will allow section on antenna polarization. George Jessop, G6JP, them to carry out a further eme test during the second half will be pleased to know that his views on horizontal versus of the contest. Charles Suckling, G3WDG, and Chris vertical are heartily endorsed in the SWOT bulletins. Lancaster, G8HDR, made further improvements to the SWOT will be keeping 4 - 2- 70 informed of American receive set-up at the Oxford University station, enabling dx happenings, and hopes to stimulate further Europe to them to copy eme signals from several stations on America moonbounce contacts by printing 4 - 2- 70 432MHz. including G3LTF. information in America. An exchange of the dates of K1WHS, one of the outstanding signals on 144MHz auroral and Es openings is also planned. moon bounce, uses a 4CX350 to drive a single Eimac 8877 Although SWOT sounds like a new kind of pest in the final I kW pa stage. The antenna is a 160-element control-with some amateurs promoting the idea of collinear array, and K I WHS recommends running letting a citizen's band loose on the amateur vhf bands. outside every 20min, even in 0°F weather, to adjust the maybe we need a SWIPE organization over here in elevation-he says it is a good way of keeping awake for Europe. late night skeds. Auroral reports Sideband repeater proposal There were 42 auroral events in the first 118 days of 1978, Details of the GB3SF, Sheffield University, sideband thus keeping up the previously-mentioned average of an repeater proposal were printed at the request of the VHF aurora every three days since the end of August. The most Committee in the March 4 - 2 - 70. Since then more than recent events took place on 1, 2, 8, 9, 16, 17, 18, 26, and 27 150 letters and telephone calls have been received about March and on 3, 4, 5, 10, 11, 12, 13, 14, 19, 23, 24 and 25 this proposal. It has also been discussed at the recent April. Repeater Working Group open meeting and the "Advan- By far the most outstanding event took place on the ced Repeater" lecture at the RSGB VHF Convention. night of 10-11 April. Richard Diamond, GM4CV1, Further publicity has also been given to the proposal in operating from the GM8FFX QTH near Aberdeen, various club and repeater group newsletters and in Short stayed exclusively on cw throughout the event and worked a total of 41 stations on 144MHz. The dx worked *PO Box 49, Aberdeen AB9 81A by GM4CV1 included three stations in Poland and five

516 RADIO COMMUNICATION June 1978 stations in Finland, significantly GW4CQT was the only be heard. The beam heading for these contacts was 5°, British station worked via the aurora. suggesting an auroral curtain well to the north of GM4COK in Edinburgh had just taken delivery of a Aberdeen. new NAG144 linear a few hours before the big event Eric Ludwig, F9LT, writes from Les Clayes-sous-Bois, started. Best dx for George was OH5LK in QTH locator France, to request a copy of all the auroral events square NU37g, a distance of 1,836km. Other stations recorded by RSGB observers since last August. F9LT has worked included SP5JC in K M56f and DL7QY in Berlin been taking note of the Geoalert transmissions made by (GM47b). GM4COK noticed two separate signals from FTA91 on 91.75kHz since that date, and offers to study G3KJY, both via the aurora but separated by more than the correlation between the geomagnetic/flare data and IkHz. the RSGB auroral reports. F9LT has also been in touch Hugh Irvine, GI3TLT, in Bangor, County Down with the Meudon Observatory and is investigating the (X022e), worked 14 stations in the same event, including possibility of making the FTA data more readily available LA3WU (CU47d), DJ9BV (EN40c), PAOCSL (CM63d), to amateurs. The present transmission can be received in SM4FXR (HT57g), SMOFFS (JT510 and, best of all, some parts of the UK on a suitable low frequency receiver OH I FA in QTH locator square LU42h. Hugh also but there are no transmissions at weekends. A review of worked G3SPJ in London who was 5/5a on 70.200MHz all the auroral events has been sent to F9LT and we await ssb. In fact there has been considerable activity on his next report with interest. 70M Hz during the recent auroral events. GM3ZBE near Lars Ericson, SMOCPA, in Bromme. Sweden, is Aberdeen, GM3YOR in Glenrothes, GI3RXV, G3TYE particularly interested in 432MHz auroral openings. He in Liverpool and G3SPJ in London have all been active reports that the following stations had 432MHz auroral during several April auroral openings. Signals on 70MHz contacts during last year: LA9DL, OH3TH, OH3XU, are generally noticed before 144MHz goes auroral, and OH40B, SM2A1D, SM2CKR, SM3AK W, SM3HZV, contacts on this band are often possible for about 30min SM4DHN, SM4FXH, SK6AB, SM7BAE, SMOCPA, after the aurora has faded on 144MHz. SMODFP, SMOFFS, SP5JC, UR2RD and UP2BBC. Peter Haylett, G3IPV, at Norwich, always seems to Lars notices that weak 144MHz auroras are often strong catch most of the auroral openings, and his persistence in on 432MHz, and vice versa. Doppler shifts of up to 3kHz monitoring 144-050MHz has been rewarded with recent have been noted, and the stronger the event the greater the ow contacts with GM3JIJ (WS59a), LA3WU. doppler shift. Lars runs 150W to a 96-element beam and SM4DHN/4 (GU79j), SM5BEI (JU72c), SM6GFS would be pleased if UK stations could listen for SM (GR I I j), SM6ESE (GS23g) and SMOBYC in locator stations on 432.050MHz during the next auroral open- square IT70b. ings. In the UK, GM3ZBE has worked G3LQR and The Propagation Studies Committee is always in- DKIKO via 432MHz aurora. Hqye any other contacts terested to receive reports of auroral contacts, parti- been made on this band? cularly when the beam headings at both ends of the QS0 have been recorded. The 4 April event started at Transequatorial success on 144MHz GM 8FFX at I 648gmt with GB3LER peaking 5/5a on a The transequatorial tests to South Africa (TESSA) have 10° beam heading. borne success, with ZE2JV working to both Cyprus and In the following report the beam heading used by the dx Greece on 144MHz. Ray Cracknell, ZE2JV, worked station is given in brackets. Stations worked included: at 5B4WR. over a distance of 5,978km, between 1800 and 1720gmt, GM8LHE 10° (10°) ; 1750, GW8FKB 30° (400); 1810gmt on Monday 10 April. 5B4WR heard ZE2JV at 1800, G8BHH 50° (40°); 1810, LA8UU 30° (20°); 1816, RST 227, and ZE2JV heard 5B4WR at RST 219F G4BWG 50° (20°); 1819, G8GXP 50° (355°); 1821, (F= doppler flutter). 5B4WR was also heard at the same SM4AIQ 50° (315°); 1829, SM4ATA 45° (305°); 2106, time by ZE2JE at RST 529-I2dB over the noise. OZ9SW 50° (30°); 2152, GM8AZS 45° (30°). Reports of On Wednesday 12 April ZE2JV worked SV1AB this type are most useful for the committee, and Charles between 1756 and 1806gmt over a distance of 6,275km. Newton, G2FKZ, of 61 Merriman Road, London SE3 SV1AB heard ZE2JV at RST 529 and ZE2JV heard 8SB, can supply the special Propagation Studies Com- SV I AB at RST 219F. The doppler flutter reported by mittee Report Forms on receipt of an sae. ZE2JV caused variations of frequency of up to 10kHz and The BBC reported a flare of hydrogen gas hundreds of affected the readability of signals to a considerable extent. thousands of miles long which shot out of the sun at Martin Harrison, G3USF, of Keele University and a 1540gmt on the afternoon of Tuesday 11 April, causing member of the RSGB Propagation Studies Committee, the worst short wave fade out for a considerable number comments that this doppler flutter must have been caused of years. This major solar eruption had little effect on the by "something moving pretty fast somewhere". strength of the auroras on 12, 13 and 14 April; all these ZE2JV also has a beacon on 144.1 I 8MHz, and this was events were weak. A call from the British Astronomical heard by 5B4BW on 9 April between 1726 and 1810gmt. Association on 13 April reported a visual aurora sighting On the same day ZS3AK copied the Lannion 50MHz at 2100gmt. GM4CVI immediately checked the GB3LER beacon between noon and 1250gmt at strengths exceeding beacon (144.965MHz) and SK4MPI, the Swedish beacon S9. SV I DH in Athens heard ZE2JV at midday on 17 (144.960MHz), for signs of a radio aurora, but no signals April. In fact, during the period 8 to 20 April at least one were heard at Aberdeen. However, a call on cw produced station heard transequatorial signals on each day. No te. weak contacts with LA and SM, but these were short- signals were heard by ZE2JV or 5B4WR on 21 and 22 lived, lasting for only 20min. It is most interesting to note April, dates on which there were no auroral reports. that for the second time this year auroral contacts have There were, of course, auroral openings on the two days been possible even when the usual auroral beacons cannot on which the te contacts occurred.

RADIO COMMUNICATION June 1978 517 4 - 2 - 70 has also been in touch with Dennis Height- man, G6DH. another te specialist from way back in 1947. REAL DX 1978

Dennis, who discovered solar noise pre-war. congra- 70M Hz aurora G3SPJ• GI3R XV 570km tulates 5B4WR and ZE2JV on their achievements over 70M Hz tropo GM 3WOJ -GU3HF N 590km the last 21 years—their 144MHz success is the culmi- 144 MHz tropo GM8M BP- DF5GX/P 1,300km nation of daily study and observation. G6DH is very 144 MHz aurora G3ZIG-UR2ROT 1,800km 144 MHz ms GM 8NCM-S M3BIU 1,340km interested in the doppler shift noticed on the recent 144 MHz te LU5DJZ-KP4EOR 6,120km 144MHz contacts. Dennis had historic contacts with 144MHz eme G3SEK• K1VVHS 4,100km ZSIP and ZS1T more than 30 years ago. using 100W 432 MHz tropo VK6KZ-VK3ZBJ 2,460km input of cw and a.m. on the old 50MHz band, but he never 432 MHz eme G3LTF-JA6CZD 13.600km noticed doppler shift on te signals. He hopes to be back on vhf soon and will certainly be there if we get 50M Hz back again. This intriguing doppler effect will obviously be the subject of further investigations, and details of this phenomenon have been sent to Edgar Mueller. YV5ZZ, Faeroes: OZ7IS, OZ3TZ and six others will be in OY who has had more than 40 transequatorial contacts in the between 20 June and 26 July. Full details are in the May last six months. More te information will be given in next 4 - 2- 70. The Glenrothes group will also be in the month's 4 - 2 - 70. Faeroes before going on to Iceland, but this expedition is already fully booked for meteor scatter skeds, including one from TF to America. Further details from Expeditions GM8NCM. QTHR. The expedition season is almost upon us and many readers have telephoned and written with details of proposed trips to far away places and rare QTH locator The grapevine squares. An expedition to St Kilda in VR square was ZE2JE runs 300W on 144MHz... VHF manager recently announced on GB2RS as being due to start at G3SEK looking for a 48 key Wheatstone.. . GM8DMZ midnight on 31 March and ending at noon on the monitored a station supposedly working the April Fool following day. This was an April Fool prank by a station expedition to St Kilda—maybe there was somebody there not a million miles from Purley. It is hoped that the after all... Which well-known repeater builder's wife following details are accurate but please do not blame locked him in the garden shack for a few hours?... GM8FFX if you do not work Iceland. the Faeroes and G3LEQ's Talkthrough guaranteed a large circulation, Andorra. All the stations listed below are known to be especially if people keep photo-copying more and increas- reliable and should make the expeditions detailed. ing the distribution—albeit with slight alterations.. . Is Andorra: PEOMOT will be active on 144225M Hz from the Glenrothes group's sked with America from Iceland a 15 July until 5 August. Skeds can be arranged by strong possibility? . . . Amplifiers with pairs of 4CX250Bs telephoning 050137490 or, by arrangement during the soon to be commercially available for both 144 and expedition. on Oscars 7 or 8. A separate expedition to 432MHz G3TYE, managing director of Polar De- Andorra by ON5UN. ON6UG and ON I DV starts on 5 velopments, just back from a flag waving, transverter August and lasts until 13 August. The callsign C310X selling trip to the USA... GM8NCM glad his new will be used and skeds can be arranged by contacting NAG144 amplifier has arrived in time for the Glenrothes Seyssens Erwin, 10 J. F. Willems Straat, B-9000 Ghent, expedition to the Faeroes and Iceland ... GM8OWX too Belgium. G8NRP of 12 Conduit Road, Abingdon. busy photographing the 14 April visual aurora for St Oxfordshire, will be in France and Andorra from the end Andrews University to'even have time to listen for a radio of June and is on the lookout for meteor scatter skeds. event ... After the G3RKL sideband repeater proposals. Eire: The Cambridge University group will be in Eire many correspondents suggest ow repeaters as the next from 23 July until 6 August. Contact G6UW, QTHR. idea. . GI8EWM has produced a plan to do away with Hull University group is planning a summer expedition to variable controls like volume etc. He suggests switched Eire, and operators G3PQY, G80MQ, G8MXH, resistor networks with Volume 1 to Volume 99 à la RKL G8JQD, G8K1J and G4FVP have applied for two El system.. . G9BF to be resurrected next month. callsigns. High power will be used on all three vhf bands. and meteor scatter skeds are sought by the group, which can be contacted at 210 Whitehall Road, Bensham, Late news Gateshead, Tyne and Wear NE8 4PU. The Edinburgh Further large-scale auroras took place on 31 April, and and District ARC also plans an expedition to Eire in July on 1.2,3 and 4 May. during which contacts were made on and can be contacted via GM8MJV, QTHR. 70, 144 and 432MHz. DK2ZF heard G3SPJ on 70MHz XL square: Tony Bettley. G8K WC, and xyl Glenys. and will transmit during future auroras on 144.120MHz G8K WD, will be holidaying in Pembroke from 18 June for crossband contacts. On 144MHz. OH, UC2 UP2. until 1 July, making QTH square XL obtainable. UR2 and UQ2 were among the dx worked by G and GM Shetlands: G8NOF, G8M ME and PE1AVU will be stations on cw. Full auroral report next month. Great operational from the Shetland Islands on both 144MHz interest at Alexandra Palace in a new transverter for the and 432MHz with high power and large antennas. For FT901 which operates on all three vhf bands and in a skeds write to G8M ME, 3 Willow Close, Lymm. solid-state Microwave Modules 100W 432MHz linear Cheshire. amplifier.

518 RADIO COMMUNICATION June 1978 1978 HF Countries Table

Station 28 21 14 7 3-5 1-8 Total Mode swl news 0R517567 160 161 186 41 80 5 633 ssb B RS35943 127 128 165 74 111 4 609 ssb B RS29641 123 137 168 73 71 4 576 ssb BRS25429 126 82 122 56 100 13 499 ssb A8841 74 96 179 55 81 0 485 ssb/cw 811535454 106 109 147 46 66 6 481 ssb/cw Bob Treocher, BRS32525 * B RS32286 121 100 116 35 56 0 428 ssb 511534740 73 85 99 50 50 7 364 ssb A9191 87 60 93 31 44 0 315 ssb A9107 37 50 83 20 44 5 239 ssb 611S20185 56 38 72 17 41 2 226 ssb News fro m abroad BRS34658 10 42 81 32 55 4 224 ssb Once again 1 am more than pleased to have had some 811537782 40 46 69 17 32 3 207 ssb BRS39162 44 50 62 9 24 4 193 ssb correspondence from a couple of swls who are more than BRS27421 0 0 108 45 39 0 192 ssb a few hundred miles from any of us. First, Eric A11S39720 24 46 65 14 19 0 168 ssb ARS39965 24 37 55 9 16 3 144 ssb/cw Trebilcock, BERS195. writes from Melbourne, where it is ARS38280 39 46 38 10 1 2 136 ssb the middle of autumn. He comments on 28M Hz con- ARS3901 8 5 39 17 15 32 1 109 ssb ditions and on the large number of European signals heard. Some rare prefixes occur in his log that many Europeans would be glad to have, cg HMOB. VSSAM. and yet another for Friday; all for contacts heard on the 9M8HG, KH6ABH and KG6JJH. Eric can hear the ZL same band, at around the same time of day and using the beacon ZL2MHF on 28,230kHz virtually every day, but same equipment. It does seem rather pointless. he has also heard N4RD and 5B4CY lately. Please, only QSL if it is worthwhile—make the report The second letter is from Craig Stoodley, SWL-8-CS- as full as possible, send an ire if QSLing direct (it makes 782. who lives in Yellowknife, which is in the VE8 region the difference). and if you are a keen dx chaser and need a of Canada. He sends information on the Canadian SWL QSL from SU on 28MHz, mention of this in the report International Club. It is a fairly new club but already they might just get you what you need. Remember, if your have a good quality monthly news bulletin and over 90 report is helpful there is an even-money chance that the members in all continents. A couple of ires to the return QSL will arrive. Robert Small mentions that he Canadian SWL International Club, Box 142 Thunder and his father. G3ALI, had been visited by VO1FG. For Bay. Ontario, Canada P7C-4V5, will bring any further those who are not 3.5MHz enthusiasts, VO1FG is information required by return. arguably the best signal out of VOI. He was in G-land visiting relatives who also live in the Ipswich area. Dx-mania Still on the dx wavelength, there are many reports this Other news time regarding the activity from Yl. YIIBGD has been Crosbie Rodgers, BRS32286, had been busy organizing heard on I 4MHz ssb around 14,210kHz operating from his radio club's open day at which they had hf, vhf and lists prepared by YU I NYP and JY5HH. The manners of Oscar stations on the air. Other attractions included a many Europeans certainly left a great deal to be desired, junk sale, bring and buy stand, and a sponsored world and this senseless behaviour must have left the Iraqi record attempt, in aid of RAIBC. on the longest two-way authorities scratching their heads trying to understand radio contact, for submission to the Guinness Book of what it was all about. Records. They were also expecting visitors from five clubs While on the subject of expeditions, the 8Z4 trip is in and around the Solway area. scheduled for 1-7 June, and VU2DK has been heard Several new reporters this time. Dave Greenhalgh, saying that he will activate VU7 (Laccadive Is) when he ARS39965, has only been listening since February and can arrange a boat. Neville Spry reports hearing that the uses a Lafayette HA350 with a W3EDP antenna system Kermadec cards have been despatched, so all those who which seems to pull in some good dx traffic. Stephen QSLd direct will be anxiously awaiting the postman. Turner, A RS37620, writes from Cheshire. where he uses HH2MC has been heard telling stations that he hopes to an ex-army R208 receiver but is always keen to borrow his be operating from Navassa Is later this year. possibly in father's 9R59DS for dx work. Robert Dowdell. July. BRS29641. uses an FRG-7 with a variety of antennas and has certainly produced a good score for the table since More dx thoughts January. George Wiltshire, BRS39060, reports that he has recently Eric Hall, BRS2742 I , is an "old-timer". His interest entertained K4SQT, who has been active for some dates back to the 'twenties. He is not a QSL card collector months as K4SQT/SU and who brought with him a large but does have one from 6HS—in those days there were no batch of QSLs to be despatched via the bureau. However. "G" prefixes. Eric currently obtains great pleasure from several valid points came out of discussing QSLing habits, listening on the bands with his BC348L and is at his rig as seen through the eyes of a rare dx station, which it most days from 0700 to 1700. would be interesting for everyone to note. A large number Ken Steele, BRS36883, had trouble with his receiver of swls send cards direct but still fail to enclose even one and has been QRT for a while as a result. He is still irc for a reply. The most worrying comment, however, waiting for VK and ZL confirmations but hopes to receive was that a number of swls send more than one QSL—one a number of cards direct in the near future. He is also for hearing the station on Monday, one for Wednesday experimenting with different antenna systems at his Derby QTH. 392 Rochester Way. Eltharn, London SE9 6LH. Keith Kerr, BRS35943. enjoyed a long stint at the rig

RADIO COMMUNICATION June 1978 519 during the Easter holidays. He ruefully bemoans missing David Gould, BRS3784, is the proud owner of a out on 3C1, TZ. VK9X and ZL/C while at university, but realistic DX160 solid-state receiver, which he uses into was a shade happier after logging CEOAE, VR6TC, 132ft of long wire. He is nearly 400ft as1 at his VK2AGT/LH, KM6FD, BV2B and 3D2UP. He also Birmingham GTH and is sure the added height has helped comments on good 28MHz conditions and suggests that VK, ZL, VS6, A4, 4S and KL7 into his logbook! because of his unwillingness to QSY from that band he Our last correspondent is Clive Williamson, may have missed even more good ones on the other BRS39136, who has G3ZUL to thank for getting him bands, but "You pays your money and takes your interested in the hobby. He is studying for the RAE, choice!". courtesy of G3NOV classes, and he and G3ZUL have Robert Small. A8841. apart from the FOO and YI recently revived the radio society at the school where they expeditions, has had another good month. 5N2 on both work. If anyone can offer them a secondhand 35M Hz and 9Y4 on 7MHz were unexpected new ones, receiver for use at the school, perhaps they could contact but again the bulk of his dxing has been on 14MHz. Clive at 14 Lawn Street, Stourbridge DY8 3UQ. A7XZZ, TR8AC2 (QSL via WB4RZN). ZL4LR/A and Because of another bumper mailbag it is only possible 7Q7LW being the best. He has also heard all 52 USA to mention by station number contributions from states thanks to WBOVQA in South Dakota. Robert has BRS37782, ARS38280, BRS20185, BRS34658, had a good month with QSL returns too—courtesy of ARS39965, BRS39I62, A9191 and A9107. OK2BFP/D2A, VP2VEH. VR4BF and FB8YF. The FB8 pleased him most as he has now received four FB8 QSLs Keep the mail flowing—hopefully it makes this page inside six months—FB8XS, FB8WE, FB8ZL and now even better reading! Deadline for the August issue— FB8YF. including all-time scores—is 17 June.

key-switch. This unit represents an important step forward in the intelligent application and use of the keyboard for sstv purposes. Further information may be obtained from Volker Wraase Elektronik, sstv scene Postfach 6522. 23 Kiel 14, Ellernbrook 6A, West Germany. The Robot 400 continues to dominate the scan-conversion scene in this country, with more and more units appearing on the bands. One P Burnett, Gel!: home-built copy using 64-1K RAMS for the memory system has been successfully completed, and at least two others using 4K RAMs are known to be actively under construction. Progress with home-built Enthusiasm for the scan-conversion mode ot transmitting and scan-converters will be reported in the next SSTV Scene. displaying sstv shows no sign of diminishing, and with developments Dave Smith, WB6ZFT, technical and sales director of Robot, recently in this field progressing at such a rate it is difficult to keep track of them. paid a flying visit to England when Robot 400 owners G3IAI. G3W W DL2RZ has introduced a companion keyboard, the KB-420, for use and G2BAR took the opportunity to meet him and discuss some of the in conjunction with his SC420 scan-converter. The KB-420 generates design features and performance of the 400. Slow-scanners will be alphanumeric displays which are stored in the memory of the SC420 interested to note that no significant changes in the 400 circuit are and may be "overlaid" on any existing picture information (for caption planned for the foreseeable future. work) or simply displayed on a plain black or white background. A A simplified block diagram for the W4ATK converter, as mentioned most useful electronic cursor is provided which indicates, in the form of in the last column, is shown in Fig 1. Data from microprocessor or a small bright area of the field, exactly where the next character will keyboard source is accepted by the 65K memory, which is controlled appear on the screen. A total of 56 (seven lines) or 32 (four lines) primarily by tri-state switching circuits. Incoming sstv is converted characters per $stv frame are available and are selectable by means of a from analogue to digital and clocked alternately into odd and even line buffer memories. The tri-state switching allows one buffer to be slowly loaded with sstv while the other is read-out at fast-scan rate. At the end Even of each line the process is inverted. This is repeated until a complete line (128 o 4 bi(s) picture is stored in the main memory. Unfortunately, to date, a full me mory ASC 11 keyboard Microprocessor sstv in circuit diagram has not been forthcoming and it is not known if the design has yet appeared in print. If anyone has any further information, SSTV Scene would be pleased to convey the details for the benefit of TRI TRI all interested sstvers. A/O meM650 mory e" 14....1.• glee .0. 1 D/A state state switch .1••• ' sw.eit.ch The proposal to change the 14MHz sstv operating frequency, cone switch cum 'A . reported last time, has received an emphatic "thumbs down" sign. The (OgItonol TTT; consensus of opinion being that this might well lead to an increased level of CIRM and even deliberate jamming of sstv signals. At present, A B C stv Oct Odd Control Fcgic 14.230MHz is the internationally established and recognized fre- line (1280 4 bets) switching quency, and many phone-only stations realizing this are prepared to me mory Line avoid the frequency and even OSY in favour of an sstv station. counter The demonstration of sstv by G2BAR on BBC TV (mentioned last time) would appear to have caught the imagination of many operators,

Fast including G4AWJ—thanks for your letter Gordon, we would be speed pleased to hear of your progress to date. To TRI stole switch 'A' clock SWL Simon Robinson is in the process of constructing a monitor (When 0-level studies allow) and would be grateful for information on Slo w Line Pixel the availability of 5FP7 tubes. If anyone can help please contact him at speed 4 clock coulter OXIMer "Repton", Batt House Road, Stocksfield, Northumberland NE43 70Z. Has anyone accepted the challenge from W9NTP to co-operate with his "moving sstv" experiments? Fig 1. Simplified block diagram of W4ATK converter Finally, to return to scan-conveners, with future development undoubtedly towards their role as a central processing unit, cw, rtty and sstv enthusiasts will find themselves "travelling the same road". This will represent just one more step towards acceptance of video • 12 Stand royd Drive. Color. Lama: BBS 7BC; display capability for the "complete" amateur radio station.

520 RADIO COMMUNICATION June 1978 WHITE ROSE RALLY 1978

A selection of photographs taken by Peter Thacker, G8NOT, at the White Rose Rally held on 19 March.

General view of the West Hall. Like the East Hall, this was packed by midday

White Rose RS members Peter Furminger, G3MZF, and Margaret Denby, G4GYL, at one of the raffle ticket stands 1 persuading David Smith, G4DAX, to take a chance, ably supported by lucky winners Walter Gardner, G3H RV, and Eric Coward, G4EYO.

Left to right: customers at the RSGB bookstall: Brian Dunn, G4FO W; Mike Shannon, G4GJN, and Lee Campbell, G3YKD ; being attended to by Hilda Laughton, xyl of G3LBO; Diana Hughes, G4EZI; Libby Lennox, G8NVO; and Joan Harris, xyl of G8MFK Hitvc Go'r rOO L Poto oe 7-114C - c -ro R H c R E

RADIO CO M MU NICATION June 1978 521 ELECTION OF RSGB REGIONAL REPRESENTATIVES

The following nominations for RSGB regional representatives to serve Region 18 - W. Ricalton, G4ADD for the period July 1978-June 1981 have been received. The Region 19 - (R. J. C. Broadbent, G3AAJ, to continue in office; composition of RSGB regions is given on page 483 of this issue. appointment held 12 months or less) Region 20 - (No nomination received) Region 1 - W. M. Furness, G3SMM Region 2- .{ R. C. Andreang. G4CMT Ballots will therefore be necessary in Regions 2. 5. 12, 15 and 16, and D. Smith, G4DAX corporate members resident in those regions are invited to vote for one Region 3 - H. S. Pinchin. G3VPE of the candidates in their respective regions. Region 4 - T. Darn, G3FGY Votes should be sent on a postcard in the following form addressed F. C. Handscombe, G4BWP to: The General Manager. RSGB, 35 Doughty Street, London WC1N Region 5 - R. E. G. Kendall, G8BNE 2AE. to arrive not later than Friday 23 June. Mark the postcard (or Region 6 - (F. S. G. Rose, G2DRT, to continue in office; envelope containing it) "Regional election" in top left-hand corner. appointment held 12 months or less) Region 7 - D. A. G. Pedder, G3LFX Form of voting card Region 8 - D. N. T. Williams, G3M DO ELECTION OF REGIONAL REPRESENTATIVES, 1978-81 Region 9 - H. J. Leonard, G4UZ Region 10 - R. G. Barrett. GW8HEZ being a fully paid up Region 11 - (No nomination received) corporate member of the RSGB resident in Region wish to record my vote in favour of Region 12 - { F. Baxter. GM3VEY F. Hall, GM8BZX Mr Region 13 - (No nomination received) as representative for Region Region 14 - (I. L. McKechnie, GM8DOX. to continue in office; Signed appointment held 12 months or less) Callsign or BAS number H. J. Campbell, GI8FOK Address Region 15 - -{ D. M. Jones, GI3KVD I. Kyle. GI8AYZ M. S. Appleby. G3ZNU In those regions for which no nomination has been received, RAs M. J. Coen, G4EOL will be appointed by Council which will be pleased to consider any Region 16 - K. F. Eastty, G3LVP recommendations from members in those regions so that suitable LK. R. Naylor, G8FUF appointments can be made. Any such recommendations should be Region 17 - L. Hawkyard. G5HD received by 23 June.

ELECTION OF RSGB AREA REPRESENTATIVES

The following nominations for RSGB area representatives to serve for Lisburn-R. Montgomery, GI4G DV. 11 Limehurst Way. Low Road. the period July 1978-June 1981 have been received. The list also Lisburn. Co Antrim BT27 4YF. includes area representatives who have held office for 12 months or Liverpool & District-C. Cartmel, G4EST. 31 Redvers Drive, less and who have indicated their willingness to continue in office for Liverpool L9 8BS. the above period. Lothian-J. McVicar. GM8GEC. 31 Lochend Road, Musselburgh, Midlothian. Acton. Brantford and Chiswick-W. G. Dyer, G3GEH, 188 Northamptonshire-S. J. Purser, G8GHZ, 2 Dobson Close, Great Gunnersbury Avenue, Acton. London W3 8LB. Houghton, Northampton NN4 OAX. Airdrie, Coatbridge. Hamilton and Motherwell-D. H. Plum' North Devon-G. Hughes. G4CG, Crinnis, High Walls. Barnstaple. ridge, GM3KMG, 7 Waterside Gardens, Hamilton. Lanarkshire. Devon. Belfast-J. T. Barnes, GI3USS. 95 Crawfordsburn Road, Bangor, Co Northumberland-E. F. Shield. G8GVN, 14 Wellwood Street, Down BT19 1BJ. Amble. Morpeth. Northumberland NE65 OEL. Berkshire-C. F. H. Young. G4CCC. 18 Wincroft Road. Caversham. N W Kent-P. F. Jobson, G3HLF. 41 The Avenue, Gravesend, Kent. Reading. Berks. Norwood and South London-G. Cluer, G4AVV. 24 Patterson Bournemouth and Christchurch-G. D. Cole, G4EMN. 6 St Road, Upper Norwood, London SE19 2LD. Anthony's Road, Bournemouth, Hants BH2 6PD. Nottingham -I. R. Brothwell, G4EAN, 56 Arnot Hill Road, Arnold. Canterbury, Herne Bay and Whitstable-M. Dennison, G3XDV. Nottingham NG5 6LQ. 5 Lambs Walk. Whitstable. Kent. Peterborough & District-L. Critchley. G3EEL, 36 Waterloo Road, Cheshunt-A. Smith, G4FAI, 28 Lambs Terrace. Edmonton, London Peterborough, Northants. N9 9UG. St Albans-B. Pickford, GrIDUS, 130 The Drive, Rickmansworth, Cornwall-B. H. Body. G8JML, Penolver, Scarcewater Vean, St Herts. Clement, Truro, Cornwall. South-east Kent-K. A. Crouch, G8KEN, 14 Victoria Road. Cape'. Coventry-W. F. M. Hahn. G3UOL, 91 The Chesils. Styvechale. le-Ferne, Folkestone, Kent CT18 7HB. Coventry. W Midlands. South-east Somerset-R. H. G. Crabb, G4GHI, Wickham Farm, Derby-M. Shardlow. G3SZJ. 19 Portreath Drive. Darley Abbey. Marston Magna. Yeovil, Somerset BA22 8DT. Derby 0E3 28J. Southport & District-N. Horrocks, G2CUZ, 34 Sandbrook Road. Glasgow -T. P. Hughes. GM3EDZ. 41 Westerlea Drive, Bridge of Ainsdale, Southport PR8 3JE. Allan, Stlrlingshire. Swansea-P. Jones. GWBCMA, 6 Gwelfor, Killay. Swansea, Glam. Grampian-A. J. Wills, GM8KMO, 1 Police Houses. Moray Street. Torbay-L. H. Webber, G 3GO W, 43 Lime Tree Walk, Newton Abbot, Elgin. Devon. Greater Manchester North-west-J. M. Horrocks. G8GTP. 17 Tunbridge Wells & District-J. C. Green how, G3PEY, 19 Dorset Wood Grove. Whitefield, Manchester M25 7ST. Road, Tunbridge Wells, Kent, Guernsey-J. E. Martin, GU3YIZ, Bonne Chance, Marais Lane. Vale, Weymouth, Dorchester and Portland-G. M. Taylor, G8HVY, Guernsey. 159 Littlemoor Road, Preston, Weymouth. Dorset DT3 6AF. Harwell-L. Sharpe, Li2HIF. 20 Harcourt Road. Wantage. Oxon Woodspring, South Avon-J. Thorn, G3PQE, 43 Hill Road, OX12 ZDO. Weston-super-Mare, Avon BS23 2RY. Highlands-G. Poole, GM40 Kt.. 25 Cromarty Drive, Milton, Kildary. Worthing. Brighton-R. A. Harvey, G3YHM. 26 Birkdale Road, Ross' shire. Durrington, Worthing. Sussex. Lichfield, Cannock. Aldridge and Sutton Coldfield-P. A. Miles. No area having received more than one nomination, no elections for G3K0B, 28 Scotch Orchard. Lichfield, Staffs WS13 6DE area representatives will be necessary.

522 RADIO CO M MUNICATION June 1978 centre in Derby, and a recommendation would be put to Council in due course. HF— Meeting held on 13.3.78 council Mr Elazley drew Council's attention to terms of reference for the HF Committee and HF Manager drawn up at the first meeting of this committee. After some amendments the terms of reference were accepted by proceedings - Council. The committee members are: E. J. Allaway, G3FK M ; D. J. Andrews, G3MXJ ; J. Bazley, G3HCT: S. H. Jessdn, G4CNY: D. Thom, G3N KS: C. J. Thomas, G3PSM (corresponding). HE Contests— Meeting on 2.2.78 A brief report of the Council meeting held on IARLI— Meetings on 19.1.78. 28.2.78 and 16.3.78 18 March 1978 The President said that a letter had been sent to Philipp Lessig. DK3LP, president of DARC. inviting him to visit RSGB in April, the visit to coincide with the next meeting of IARU Working Group, when delegates for the Hungary conference would receive their final briefing. Interference— Ho com ments Present: Dr D. S. Evans (President, in the chair). Lord Wallace. Mr D. Membership & Representation — Meeting on 11.2.78 H. Adams, Mr A. M Allan, Dr E. J. AIlaway, Messrs J. Anthony. P. The question of reduced/waived subscriptions had been considered Balestrini. J. Bazley. T. P. Douglas. W. F. McGonigle. B. O'Brien, R. F. and the following statistics at February 1978 noted: waived 195; Stevens. G. M. C. Stone. C. J. Thomas (members of Council), D. A. reduced 647. This accounted for a loss in subscription income of Evans (general manager/secretary). A. W. Hutchinson (editor). Mrs H. E2.864 and the position would be further considered. M. Allin (minutes secretary). Microyvave— Meetings on 28.1.78 and 12.3.78 Apologies for absence were received from Messrs D. J. Andrews, The committee members are: J. Anthony, G3KOF ; D. S. Evans, P. F D. Cornish. C. H. Parsons and W. A. Scarr. G3RPE, B. Chambers. G8AGN: H. Griffiths, G4CNV; D. Hayter, G3JHM; K. S. Hutchinson, G4ALN: H. W. Rees, G3HWR; C. W. Form of agenda Suckling, G3WDG : M. H. Walters. G3JVL. The President drew attention to the new form of agenda which would Mobile & Exhibition— Meeting on 13.7.78 enable the work of the Society's committees to be discussed in greater M r Balestrini said the committee was happy with arrangements being depth made by Mr Hawkyard. G5HD, the exhibition organizer, for the Financial report Alexandra Palace Exhibition. Propagation Studies— Meeting on 13.1.78 In the absence of the treasurer, the general manager reported that it had been agreed to hold an interim audit within the next six weeks, as a It was noted that Messrs C. J. Thomas and A. Taylor were attending the IARU Region 1 conference in Hungary as representatives of IARU, not preliminary step towards ensuring a smooth audit at the end of the financial year. RSGB. Rayne! The surplus of income over expenditure was being maintained as a result of the increase in recovered subscriptions and new members, There were no minutes of the last meeting due to the secretary having advertising revenue, sale of books and a decrease in overall recently suffered a heart attack. Mr Balestrini outlined his reasons for declining chairmanship of the expenditure. Raynet Committee. He felt that 10 years was long enough for one General manager's report person to hold this position. Also his terms of reference as emergency Mr Evans spoke of the continuing heavy pressure of the work which com munications manager stated that preferably he should not be was being dealt with at HO. Correspondence and membership queries chairman of the committee, and Mr Balestrini felt that the two were up to date, although recent staff sickness had caused some critical functions could clash at times. periods. The new telephone system should be installed in May and this Technical & Publications— Meeting held on 11.1.78 would alleviate some of the problems. Mr Stevens reported that considerably larger quantities of books were The proposed move of the packing department in to the front being sold, and reprints and new editions were being undertaken. basement had been approved and structural work would proceed Agreement had been obtained from Ron Ham to make use of soon. material he had collected in the book on the technical development of amateur radio, on which Mr G. R. Jessop, G6JP, was working. Repeater jam mers Telecom munication Liaison Committee— Meeting on 2.2.78 The general manager reported that he had received several written The following recom mendation of the committee was approved reports of repeater jamming activities, but to date none of the "Should any member of the Society be successfully convicted for amateurs involved was a member of the Society. offences calculated to bring the name of the amateur radio service into Mr O'Brien said this subject had been discussed at length by the M & disrepute, the details of the case should be brought to the attention of R Committee and RRs and ARs had been asked to pass on information Council". about prosecutions so that a list could be compiled at HQ. VHF— Meeting on 14.1.78 It was stressed that the Society should act only in cases of definite Mr Douglas reported that a repeater co-ordinator had now been convictions and not merely on hearsay. appointed within this committee to assist HO and provide information The President reported on a case recently where two jammers were for "4-2-70". Mr Stone said that 685 persons had paid to attend the located and eventually reported to the police. Mr Stevens said that the VHF Convention: in addition to the trade representatives and 18 trade Home Office was reluctant to prosecute because those giving evidence exhibitors. It was planned to hold a similar event on 10 March 1979. were police rather than officials of the Post Office or Home Office. VHF Contests-1 Meetings on 26.1.78 and 22.2.78 Dr Evans commented that one possible reason for lack of action in Mr Stone reported that an open session on contests had been held at the case under discussion was that the policemen involved may not the VHF Convention. The adaptation of rules was constantly under have been technically qualified to give evidence against the jammers. review. Mr Stevens said the Society should be seen to be doing something positive or it would be thought that the Society was sympathetic Council/com mittee me mbers' links with com mercial towards offenders. The delays in Whitehall were placing the Society in activities an embarrassing position. The President stated that Mr C. J. Thomas had associations with a Considerable discussion took place on various possible courses of commercial organization and this raised the general question of such action. associations making the Society vulnerable to criticism, especially when one had access to certain confidential matters. Revie w of com mittee business After discussion it was proposed by Lord Wallace that candidates for Mr Anthony raised the question of new committee meetings being held election should declare their interests in any particular firm and prior to approval of the new committees at Council's first meeting of withdraw from meetings where confidential matters were under the year. discussion. This was seconded by Mr Thomas and agreed After discussion it was felt that Council should in future discuss unanimously. committee membership during its last meeting of the year. officers of each committee to be endorsed by Council after election by the Correspondence committee. The general manager had received a letter from the Edinburgh & Education— Meetings held on 7.1.78 and 11.3.78 District ARC, proposing that a GM4HA M shield be presented to the Mr Anthony mentioned a proposal for the establishment of an RAE highest placed Scottish station in the RSGB's 2m open contest held

RA DIO CO M M U NICATIO N June 1978 523 around September. The letter would be passed to G4B E L. chairman of this event was incorporated into a larger occasion; Alexandra Palace, the VHF Contests Committee, for consideration of the administration perhaps? , necessary for such an award. Please do not misunderstand my intentions. as I do not in any way Two proposals from the ARC of Nottingham were discussed. One wish to malign the excellent organization work of those involved. The referred to the Articles of Association and suggested various amend- point I wish to make is that the RSGB VHF Convention is now ments, and the other asked for the AGM to be held during the weekend. extremely successful, if not too successful, and that it is time to think The letters would be referred to the M & R Committee. again. R. J. Constantine, G3UGF Membership and representation It was resolved: (i) to accept reduced subscriptions from 11 members: (ii) to waive the subscriptions of two members; (iii) to grant affiliation to: Mitre-Bedford Amateur Radio Club. WA1PHY, Bedford, USA; North Kent Repeater Group, Sidcup, Kent; RAF Akratiri Radio Club, ZC4AK, BFPO 57; Walsall Amateur Radio obituaries Club, Walsall, West Midlands. (iv) to approve the election of Mr R. J. C. Broadbent, G3AAJ. as regional representative for Region 19.

The Society records with regret the deaths of the following radio amateurs:

Mr M. Brown, G2YP your opinion Morrie Brown, who died on 26 April, had recently returned from Australia where he had been active under the callsign VK2OR. He was well known in the UK and Australia for his experimental work on hf antennas.

Mr D. C. French, BEM, G3HSE RECIPROCAL LICENSING WITH THE REPUBLIC OF ZAMBIA Mr French. who died on 13 April, aged 79, was a prominent and active The Editor member of the Society for many years. Radio Communication Sir— I am writing on behalf of the Radio Society of Zambia to inform Mr L. Honeywill, G4PJ your members through the "Your Opinion" column that although a Les Honeywill died on 15 April. He was well known on 80m and 160m reciprocal licensing agreement exists between the UK and the Republic for his booming voice and for his kindness on and off the air. He was a of Zambia it is not being honoured at the Zambian end. Any licensed well-liked local personality and encouraged many youngsters to join amateurs coming to Zambia have almost no chance at all of getting a the ranks of radio amateurs_ 9J2 call for the foreseeable future due to the uncertain political situation here. Mr P. Lowth, ZE7JX C. R. Bayliss. 9J2CB G3WKL, (secretary) Peter Lowth, who had previously held a VO2 callsign. was well known for his top band activities throughout the world, having many contacts COST OF AMATEUR EQUIP MENT with W1 BB via this mode. As an ex-telegraphist, he was a very keen cw The Editor man, although in later years he had eased up on hf activities in Radio Communication preference for top band. Oscar and vhf in general. Sir—At our last group meeting several members expressed concern at the rising cost of amateur radio gear. This is a subject frequently "aired" Mr D. Poole, G3AQ W so it appears to concern many in the UK apart from the OMs. Danny Poole died on 7 April, aged 65. He was a life member and former Examples of the remarks are: Why does a piece of gear selling for 700 area representative of the RSGB, and a member of the RAIBC. He was dollars in the USA cost £700 in the UK? Why is the trade-in allowance an enthusiastic member of the North Staffs Raynet Group from its on nearly-new top quality gear so poor? Why is there never a sale of inception, and a well-known personality in the Stoke-on-Trent area. radio gear ?—even the sophisticated London stores have annual sales. His activities in recent years had centred on vhf and uhf operation. Why is there no price competition among the retailers of similar radio equipment? Why do companies which readily accept credit cards seem Mr J. Proctor, G2AKC amazed when a cash discount is asked for by a personal shopper? Just Mr Proctor, who died at the beginning of March, was one of the old how much does an FT101 or TS820 cost in Japan? Does the ARRA timers of the G5SN net. hold a monopoly which operates against the financial interests of radio amateurs? Mr S. T. R. Redward, BRS30948 The cost of equipment nowadays must discourage many potential Sid Redward died on 8 March aged 47. He was an enthusiastic swl. enthusiasts while a cut in price might stimulate the old-timers to buy a although business pressures restricted his activities, and a member of few more bits and pieces. Yeovil Amateur Radio Club for several years. Ayr Amateur Radio Group. We have also been advised of the deaths of: VHF CONVENTION Mr G. W. Hayward, G8BD, on 18 February; The Editor Mr R. Lester, GD3UYI; Radio Communication Mr P. W. Martin, G3P W M. on 18 February; Sir—The VHF Committee and all concerned are to be commended for Mr D. S. Stringer. G3S WA, on 5 January. their work in organizing another highly successful vhf convention this year. The trade exhibits were geared to the vhf/uhf devotee, and the lecture programme was of a high standard. It covered a wide spectrum of interest and catered for the varying technical skills of those Looking ahead attending, myself included! It is also a measure of the convention's success that it was almost 11-14 July—Radio Receivers and Associated Systems Conference. impossible to park, at the Winning Post, by 11am (official start time) Southampton University. Details from Peter Elliott. IERE, 99 Govver and that the lecture rooms were so full that I was unable to gain entry to Street. London WC1E 6AZ any of them. I have long since learned the benefit of taking my own 15 July—BARTG Convention, Harpenden Public Hall, Harpenden, food to-this venue, in order to avoid the long queues, slow service, poor Hens. choice and expensive prices. However, it came as something of a 29 July—Region 15 ORM, Belfast. shock, for myself and the three other amateurs with whom I had 17 September—IO W **get-together", Alverstone Manor, Details travelled from Yorkshire, to discover that we were unable to attend the from G3KPO. lectures that we had come to hear. 24 September— Welsh Amateur Radio Convention, Oakdale Com- For all of us. and I am sure many more, it was a 16-hour day and a munity College. Blackwood. Gwent. Details from GW3KYA. journey that we will not be contemplating next year. Is it not time that 2-4 November—ARRA Exhibition, Granby Halls, Leicester.

524 RADIO CO M MUNICATION June 1978 RSGB SLO W MORSE PRACTICE TRANS MISSIONS

These slow morse practice transmissions are sponsored by the RSGB. Alterations and additions to this list should be sent to the honorary organizer. Mr M. A. C. Me al rayne. G3KGU. 25 Purlieu Way. Theydon Bois. Essex.

Clock Callsign M Hz Mode Town Clock Callsign Mhz Mode Town time time

Sundays Wednesdays 0900 . G3WNR. 145.600 . F2/F3 South Shields. T & W 1-810 .. A2 3-550 .. A2 omni• direct 1135 . G3RAF Locking. Avon 1015 G3CGD 1.875 . Al /A3 Cheltenham, Glos 145.250.. A2 1030 G3OH M/A 144.180.. Al /A3J Birmingham omni•direct 1 Accrington. Lanes 1030 G3NPB 1.875 .. Al St Ives, Cornwall 1830 " e rCZ . 145-525.. F2 Blackburn. Lanes 1100 G2FXA 1.900 Al /A3 Stockton •on-Tees 1130 G38LS 1.920 .. Al /A3 Osney. Oxford 1830 G3ZOS . [1.930 .. Al /A3J Darwen. Lanes 1200 G3HVI 144-750 A2/A3 Stoke•on•Trent, Staffs (usb) omni -direct 145.525.. F2 1230 GU4CHY 144-500 .. A1/A3J St Peter Port, Cl 1900 G3ULY .. 1-826 .. Al /A3J Culgaith. Cumbria to north 1900 G4FKZ .. 3 575 .. Al /A3 Chadderton, Lanes 1500 G4EH W 144.250.. Al /A3J Peterborough 1 1.810 . A2 3-550 .. A2 to soulh•west G3RAF Locking, Avon 1930 .. 145.250.. A2 1815 G40V2 1.915 . Al /A3J Leeds. Yorks 1930 G3LO W 144-160 .. Al /A3J Birmingham omni-direct Omni-direct 1930 G3ZYY .. 145-525 . F2/F3 Plymouth. Devon 2000 G8OU .. 1.970 . Al London N22 2000 G3BPE .. 1.975 Al /A3 Bexley. Kent 2000 G3SWP .. 144-200 A2/A3J Doncaster. South Yorks omni-dnect 2000 GM4DSZ 144-230. Al /A3J Aberdeen to south-south west Mondays 2015 G3WVJ .. 1.845 .. Al /A3 Staines. Middlesex 2100 G3HVI .. 144 750 .. A2-A3 Stokeoon•Trent. Staffs 1-810 A2 3.550 .. A2 omni•direet 1135 G3RAF Locking, Avon 145.250 .. A2 2130 G3VWL .. 144.160.. Al /A3J .. Worthing. Sussex ornni -direct 1830 G3VBI {1.910 Al /A3 . Goole. South Humberside G3LR Accrington. Lanes 1830 145-525 .. F2 Thursdays 1-G3NCZ Blackburn, Lanes 1-810 A2 1-930 . AI /A3..I 1830 G 3ZOS (usb) Damon. Lanes 1135 G3RAF 1550 .. A2 Locking, Avon 145 525 .. F2 145 250 .. A2 mini-direct 1900 G3ZRZ . 1.975 . Al /A3 Blackpool, Lanes 1830 G4BNA .. 1590 .. Al Swindon. Wilts 1900 G4FKZ . 3•575 .. Al /A3 . Cheddenon. Lanes 1830 .. G3NC 1-968 . Al Swindon. Wilts 1900 G4BNV . 144-170 .. Al /A3J (»try St Mary. Devon Acciington. Lanes horizontally to south-east 1830 .. 141525 .. F2 1214, Blackburn. Lanes 1-810 .. A2 f 1 930 .. Al /A3J 3.550.. A2 1930 G3RAF .. Locking. Avon 1830 G3ZOS ( usb) Darweh. Lanes 145.250 .. A2 145.525 .. 12 { 'omm-direet 1900 G3BLS 1.920 .. Al /A3 . 1930 G3ZYY . 145-525 .. FVF3 .. Plymouth, Devon Osnev. Oxford 1900 G3ZRZ . 1.975 .. Al /A3 • Blackpool, Lanes horizontally to south-west 1930 GI3SXG .. 144.110.. Al /A3J .. Newtownaids, Co Down 1.810 .. A2 2000 G3IBJ .. 1.910 .. Al /A3 .. Southampton. Hants 1930 G3RAF . 3-550 .. A2 Locking. Avon 2000 G3XVVZ . 1.910 .. Al /A3J ... Mansfield, Notts 145.250 .. A2 2000 GM4ELV 1570 .. Atrochar. S/Clyde 0mM-direct 1.875 .. Al /A3J 1.875 .. Al 2030 G3ASR/A 1144175 .. AI /A3J .. Harrow. Middlesex 1930 .. G3ASR/A 144.175 .. Al /A3J . Harrow. Middlesex omm-direci (Isb) vertical (island 3rd weeks of omni•dilect (Isb) month only.) vertical 2030 G3YMJ .. 1.975 .. Al /A3J .. Harlow. Essex Plymouth, Devon 2130 G3101 .. 145-300 .. F2/F3 .. Lancing, Sussex 1930 .. (i3ZY). .. 145-525 F2/F3 2030 .. G3KGU 1.915 .. Al /A3 .. Theydon Bois, Essex 2130 .. G3L01 .. 145-300 F2/F3 Lancing. Sussex

Fridays Tuesdays 1-810 .. A2 3.550 A2 11 810 .. A2 1135 G3RAF 145.250 A2 Looking. Avon . 3.550 .. A2 1135 G3RAF Locking. Avon omni-direct ' 141250.. A2 1830 .. G4CRI {1525 . Al Helston. Cornwall omniodireci G3LR Accrington, Lanes 1830 G4BNA o. 3.590 .. Al .. Swindon. Wills 145-525 F2 1830 • {G3NCZ Blackburn. Lanes G3LR Accrington. Lanes 1830 • • 145.525.. F2 • • 11 .930 Al /A3) G3NCZ Blackburn. Lanes { 1830 G3ZOS (usb) Darwen, Lanes 1830 G320S 1.930 .. Al/A.3J 145 525 F2 .(usb) Darwen, Lancs 145.525.. F2 1900 G3NPB 1-875 Al Su Ives. Cornwall 1900 GU4CHY 144.500 Al /A3J St Peter Port, Cl 1-810 A2 3.550 .. A2 to north 1930 G3RAF Locking. Avon 1900 G4FKZ 3-575 .. AI /A3 Chadderton. Lanes 145-250.. A2 omni•direct 1930 G3POF . 144360 . F21 F3 Farnborough. Hants lo norih•east 2000 G310F .. 1.875 .. Al /A3 Marlow. Bucks 2130 G3VWL 144-160.. Al /A3J 2000 G4AEU .. 1.910 .. Al /A3 Southampton. Hants Worthing. Sussex 144-110 Al /A3J 2000 G4EZA 145.525.. F2/F3 Colchester, Essex 2200 G3AWL Pelee.). Co Durham to south omni•direct vertical 2030 G3IR M .. 1.975 .. Al /A3 Bury St Edmunds, Sultoik 2030 G4FFC 145.575.. F2/F3 Penenhall, Beds Saturdays to south 2030 G3OH M/A 144.180 .. Al /A3J . Birmingham 0930 G2FNK . 1.930 .. Al /A3J . Stamen, Middlesex 2045 G4AEU 145-550 .. F2/F3 Southampton. Hants 1.810 .. A2 omni•direct vertical 1135 G3RAF 3.550 .. A2 2200 G3A WL 144.110.. AI /A3J Peterlee. Co Durham .145-250 .. A2 in tnnih 1ornai-direct

RADIO COMMUNICATION June 1978 receive the VHF Contests Committee Cup. Certificates go to the leaders and runners-up in each section. r contest news G2HIF Poso Callsign Points QS0s ORA Best dx Km Pvvr out

1 G4BEL/A 2.638 34 AN171 G8LEF 222 40W 2 G3SBV/P 1.124 23 AL51 G4DGU 101 60W 3 G4DDC/P 1.118 21 ZL18 G3DAH 147 40W in 4 G3FZL 846 20 Z150 G6XM 117 10W 432M. Hz Open Contest results 5 G8GP 828 21 2150 G4DGU 89 10W 6 G3C0J 774 18 ZL37 G8ACE/P 71 25W The 432M Hz Open attracted 17 fewer entries than last year in spite of 7 631102 750 21 21.50 G4BRS/P 94 40W its being scheduled as the major 432M Hz for 1978. Only 16 portable 8 G3G0C/P 722 14 ZN62 G4BEL/A 175 100W in and 12 fixed stations sent in logs, two more than the minimum 9 G31.1UP/P 700 16 2126 G3SBV/P 78 6W requirement to support the two sections. 10 G3POY/P 657 11 ZN18 G3GC1C/P 105 30W in Very poor conditions prevailed for most of the time and the lower 11 G3VCT 618 15 2137 G4BEL/A 66 4W 12 G3HCW 308 9 ZN24 G4FXW 45 60W in than usual scores may have discouraged many stations from sending in 13 G4CGS 273 7 ZN11 G3PC1Y/P 83 6W a log. A few PAOs were worked by stations near the east coast, but with 14 GW4ASR/P 240 2 YL23 G3AUS 130 4W one exception the best dx was well under 500km. Comments were very 15 GBCTT 232 7 AL41 G4BEL/A 66 2W few; complaints about bad signals were minimal, and the general G3MCS 670' 15 3W impression created was one of lukewarm enthusiasm by the faithful. The leading stations are to be congratulated upon their victories. 'estimated from radial scote Certificates of merit go to the winners and runners-up in each section. and the 1951 Council Cup Trophy to the leading station overall. Affiliated Societies Team Contest 1978 G2H1F results This year's ASTC event—the third under the present "team" rules—has FIXED STATIONS proved once again the popularity of the new-style contest. To the Posn Callsign Points OSOs QRA Best dx Km Kerr out casual listener, the cvv section of 3.5MHz on the afternoon of 15 1 G3VPK 608 94 AL14 GO2HDZ 430 160W January must have sounded like complete bedlam; however, order and 2 G3WOH 315 48 YN47 G8BIS 310 200W discipline reigned supreme (we are, of course, self -trained in the art of 3 G8GP 283 73 2150 GD2HDZ 413 40W communication by wireless telegraphy) and, as a result, the leading 4 GD2HDZ 176 16 X068 G3YCW/P 430 300W in scores are well up on previous totals. About 18.000 0S0s were made 5 08001 161 49 ZL47 G8FIS/P 325 IOW during the four-hour session in a bandwidth of 80kHz—that is nearly 6 681WA 138 25 ZN18 PE113HE 365 10W 7 G4FOX 108 32 2M26 GW3UBX/P 116 IOW one OSO per minute per kilohertz I Club entries have increased from 51 8 G8CTT 86 32 AL41 GW3UBX/P 274 10W in 1977 to 61 this year, and the number of individual logs has jumped 9 G4FRE 81 23 ZM33 G3VPK 174 IOW from 218 to 291. 10 G3TAL 46 14 21(14 G8OHM/P 180 100W The leading society, and this year's recipient of the Edgware Trophy, 11 G3FIJ 40 10 AL05 GW4ASR/P 315 10W is the Stockport Radio Society, whose -A" team —G3 WPF. G3N OM, 12 G8ITS 34 24 ZL40 G3NNG/P 102 40W G4BUX, G3PEK/A and G3FYE—a massed 6,442 points to give them a clear lead over the runner- up, the Southgate Radio Club. with 6.165 PORTABLE STATIONS points. In third place is the Addiscombe ARC which scored 5,740 Pose Callsign Points QS0s ORA Best dx Km Pwr out points. 1 G3PMH/A 643 126 AM71 PA6THT 460 400W With the exception of two clubs, this year's -top 10" is similar to last 2 GW3UBX/P 563 83 YM44 GJ8KNV/P 356 75W year's, but with the positions somewhat changed. Stockport has 3 G3NNG/P 524 103 ZL33 PAOEZ 466 400W moved up from 6th in 1977 (and 33rd in 1976) to the number one 4 G8FIS/P 471 56 2055 PAOEZ 465 100W 5 G3YCW/P 456 102 AL33 GD2HDZ 420 300W position; Southgate has retained the second slot, while Addiscombe is 6 GW4ASR/P 450 60 YL23 G3DAH 325 100W up from fourth to third. The two newcomers to the top 10 are the 7 G8OHM/P 381 79 YM50 GJ8KNV/P 347 50W Government Com munications ARC, moving from 15th to 6th place, 8 G3PCIY/P 380 58 21,118 PAOWOS 421 100W and the White Rose RS in 7th position—they did not enter last year but 9 G400C/P 378 103 ZL18 PAOEZ 385 200W were 8th in 1976. The two "drop-outs" are Cray Valley, falling from 5th 10 G6YB/A 343 57 Y149 PAOEZ 517 400W to 24th; and Reigate, who were 9th in 1977 but did not enter this year. 11 G3G0C/P 312 66 ZN62 G3AUS 180 300W 12 G8AYY/P 276 63 ZM71 G3BW 305 IOW although several of their members were active during the contest. 13 G4ERP/P 248 58 ZLO1 G3BW 313 8W The leading individual, by a substantial margin, is G3WPF, of 14 G8GMC/P 212 50 Z153 G8FIS/P 330 IOW Stockport, with a checked score of 1,592 points from 192 CiS0s—that 15 G3UUP/P 176 64 ZL26 GW4ASR/P 177 10W is an average of over 48 0S0s/hour. Runner-up in the individual 16 G8JAY/P 134 37 YM36 G3VPK 240 10W listing, as he was last time. is G3RTE with 1.385 points from 150 contacts. Checklogs acknowledged with thanks from 0400U and G3NAQ. Equip ment LISTENER SECTION As in previous years. Japanese equipment dominated the scene, Potin Station Points QS0s ORA Best dx Km although a number of KW2000 transceivers, Drake and Heathkit rigs 1 A9090 110 30 2M63 GD2HDZ 290 2 BRS33823 57 25 ZL27 GGYB/A also featured. There were a couple of homebrew transmitters in use, as 3 BRS15822 44 22 ZL40 G3GOC/P well as the odd CR100 and HRO. G3MCK again used his co/pa transmitter to make a reasonable score. Antennas varied from dipoles and inverted-Vs to trapped verticals and short lengths of wire.

1,296MHz Open Contest results The logs Most of the logs were legible, and complete with a properly corn piled It is difficult to say how the timing of this event—the Saturday cover sheet, but as usual there were a few which were either difficult to evening before the 432M Hz Open —influenced the number of entries, read, and/or presented on odd pieces of paper. with the "in" and "out" but lengthwise it was about right for the level of activity. Like the columns reversed, or in red ink. These may seem like minor irritations, 432MHz contest, it would undoubtedly have attracted more entries but when one is working through a pile of logs (and it was a large pile had it been held later in the year. Conditions were flat; no Continental this year!) those which do not conform to the normal standard take stations were worked and no best dx reached 250km. While the general longer to deal with as they are more difficult to process. Log and cover level of activity on 1,296MHz continues to increase only very slowly, sheets are now available free of charge from RSGB Ha (please enclose the band remains popular among its devotees. Several contestants sae), so there should be no excuse next year I It would help the contest would like to see the 1,296MHz cumulatives restored. adjudicator if (a) the name of the club was written on the cover sheet The band is still a long way from realizing its full potential, but as on each of the individual logs, and (b) the overall cover sheet (with the more stations go for higher power and bigger antenna gains, the longer membership declaration) listed the callsigns and claimed scores of all distance contacts become more commonplace. the stations in the club entry. The March & District Radio Amateur Society gained a convincing Points have been deducted from most claimed scores, mostly victory, with more than twice the score of their nearest rival. They because of incorrect claiming of the AFS bonus, or the bonus not being

526 RA DIO CO M M U NICATIO N June 1978 confirmed by receipt of the corresponding log-there were quite a few "How about a 2m phone version to involve the Class B licensees ?"- stations participating in the contest whose clubs did not submit entries G3ZLO (VHF Contests Committee to note)) and in those cases the AFS bonus has not been allowed. Wrong "Greatly appreciated the courtesy and consideration shown by most callsigns also cost some entrants a lot of points-more careful operators to a fairly new G4 participating in his first cw contest. -- checking of the logs before submission would improve the accuracy in G4GGV. many cases. One G2- plus- 3 lost a considerable number of points "My first contest for over 10 years l"-G4DC. because his callsign was consistently misread by other entrants. Final A few facts and figures Judging by the large number of entrants who expressed complete satisfaction with the contest as it now is, there would appear to be no 1976 1977 1978 need to change the rules in the immediate future. Only the timing Winning club score 4.191 5.488 6,442 comes in for comment, a few would prefer Sunday morning to the Leading individual score 1.155 1,403 1,592 afternoon, but on balance the HF Contests Committee believes that the Number of stations scoring over present timing is best. Incidentally, the result of last year's invitation by 1.000 points 16 29 45 G3IAS to clubs was the receipt of a solitary postcard expressing a preference for the present timing! Com ments Having mentioned G3IAS in the preceding paragraph, this is "Just the right duration not to cause domestic distress. More contests probably an ideal opportunity to present an open -vote of thanks" to of that duration and timing please."-G3YDX. Andrew for his efforts in connection with this contest. The new-style -Please leave rules exactly as now -changes could not improve such a AFS team event was very much his idea, and the popularity and successful contest."-G3YMC. (Similar comments were made by success of the present-day contest is largely due to his enthusiasm and many other entrants.) his management of the rules and results in recent years.

SOCIETY TOTALS Number of Posn Society Total Stations contributing to score entries 1 Stockport RS (A) 6,442 G3WPF G3NO M G4BUX G3PEK/A G3FYE 5 2 Southgate RC 6.165 G3RTE G3YDX G3KTZ G3XTJ G3RWL 5 3 Addiscombe ARC 5,740 G3ROZ G4ALE G3SJX G3UFY G4CDY 5 7 4 Bracknell ARS 5.045 G3YMC/A G4ALG/A G4BRK/A G4AUC/A G3YHG 6 5 Crawley ARC 5,020 G3JKF G3TR G3YVR G3TIR/A G3G RO 6 Govt Comms ARC (A) 4,954 G8DV G3SSO G3LEJ G3MZV/A G3SNN 5 7 White Rose RS 4,577 G3XUD/A G3ZBA G3PSM G4DXA G3YEE 8 8 Maidstone YMCA ARS 4.505 G3ZWH G3ZSU/A G3ORH G4DUT G4AXD 6 9 Hereford ARS 4.419 G4CNY G3WRA G3WRO G4FFD G3RJB 1 o Surrey Radio Contact C 4,282 G3MCX G3BFP G6LX G3RJW G4FUU/A 9 11 Grimsby ARS 4.070 G3VIP/A G3HTI/A G3RSD G4EBK G2A.18/4 e 12 Edgware & D RS 3.955 G3SJE G3PSP G3GC G3VW G4AEM 5 13 Sutton & Cheam RS 3.650 G4CWH G3LCH G3DNJ G3CWL G2DMR 7 14 Stourbridge & D ARS 3.544 G601 G4IP G4GME G3JEI G4GGU 15 Shefford & D RS 3.527 G3FJE G4ORS G2DPO G3DOT G5CAX 5 16 Manlesham AS 3.510 G48P0 G3RPB 6312E G3TLY G3INU 6 17 RNARS Portsmouth 3.425 G3JFF G3LIK G& W/ G4FIV G3BTO 7 4 18 Verulam ARC 3.350 G4BOU G3JKS G4DUS G3LXP/A 19 Cheltenham ARA 3.299 G5BK/A G3LP G3ZKN G3JFH G3CJ 7 20 Echelford ARS 3,280 G3KKI) G2FNK G3ZXA G3MCK G3YCO 7 21 Cattenck Garrison ARC 3.200 G4CJU 6311311 G3EJF G4EXV G3FM W 5 6 22 Leicester Coll ARS 2,985 G3ORY G4FIE G3SOC G4AR1 G3LVZ 23 Dunstable Downs RC 2,900 G4ENA G3HJF G3HAL G3BLP G3USE 5 4 24 Cray Valley RS 2,895 G4FAM G2M1 G3XRX G3JJC 25 Thames Valley ARTS 2,855 G3JEO G2K1 G3G HS G8SM G3BPM 6 26 Southdown ARS 2,851 G3MHF G3KLX G8SC 63 WOK G3YYF 7 27 Stockport RS (B) 2,710 G3KAF G3RUG G4BJU/A G4ECI G4FAS 5 4 28 Leicester RS 2,700 G3LRS G3HYH G4ERT G3ZJS 29 RNARS HMS 13eltast 2.625 G4E0K G4FRN G4DJN G3PZP G4BVA 7 6 30 Glenrothes & D ARC 2,580 GM3ZSP GM4GRC G M4EJI GM4BRM GM3PF0 31 Conway Valley ARS 2.567 GW3GRY GW3CW GW3JI GW3MOK GW3YLI 5 32 ARC of Noningham 2.565 G3SJJ G4ECY G4DVW G3WFV G4AFJ 33 Crawley Court ARG 2.557 G3OGY G3HOX G3RDO G3LMH G3HRH 34 Reading ARC 2,482 G3WGV G3AKF G4ELY G4A0L/A G4ELD 5 4 35 Wirral ARS 2.360 G2FOS G3N WR G3UJX G3EGX 36 Horsham ARC 2.340 G3TN0/4 G3SWC G4FUP 3 4 37 Oxford & D ARS 2.245 G4AZN G3ZZR 6818 G3BLS 38 Torbay ARS 2.147 G3TLK G4ELZ G3SNU G4FKU G3LHJ 5 4 39 Hornsea ARS 2,140 G4DC 04811F G3TLI/A G4CHH 4 40 Leyland Hundred ARG 2,105 G3X11 G3VYV G3H KU G3WYY 41 Maidenhead & D ARC 2.095 G3FVC G3TWG G321.0 G4GGV 04621 5 42 Swansea ARS 2,060 GW30AY GW3IN W 2 43 Govt Comms ARC (B) 2.045 G3AUU G3AGF G4BEZ G3LGF G3IFB 44 Oxford Univ RS 1.930 G4BUO/A G3OUR/A G3YGF/A G5BU W 4 3 45 Stevenage & D ARS 1,900 G3OVT G4DDX G3TIK 46 Farnborough & D RS 1.715 G3VAA G3SVL G3MKG G3TMO 4 47 Yeovil ARC 1,490 G3ED W G3CMH G3BEC G4FYS G4G NV 6 4e Kingsway Tech Coll RAC 1.483 GM4AGS GM3ZXE GM4BAG GM4CUZ 4 49 Clifton ARS 1.365 640E41/ G3JKY 2 50 1 Merthyr Tydfil ARC 1310 GW3MPB GW4FXF 2 1 RNARS Rosyth 1.310 GM3UM GM3KPD GM3HUN 3 52 Bromsgrove & 0 ARC 1,252 G4A.AL G4DHH G2CLN G3R13L 4 53 Dover RC - SE Kent (YMCA) RC 1,115 G30 W0 G3MLO G3YXX/A G4EGO G4E0J 5 54 West Kent ARS 1.100 G3410 G4FOC 2 55 Bury RS 982 G3BRS G4FOT G4FOE 63G VU 4 1 56 RNARS Yeovitton 790 G2KV 57 RNARS Chatham 660 G3WP G3JPX G4CZD 3 1 58 South Manchester RC 605 G3FVA 59 Stockport RS (C) 545 G4FTP G3DNX G4FFW G3NUO 4 60 RNARS Plymouth 430 G3VNG G3UVS 2 61 RNARS Faslane 347 GM4ELV GM4FVO 2

Checklog acknowledged with thanks from G3OLB

RA DIO CO M M U NICATIO N June 1978 527 INDIVIDUAL SCORES

Posn Callsign Score Society Poso Callsign Score Society Poso Callsign Score Society 1 G3WPF 1.592 Stockport RS (A) 93 G2KV 750 RNARS YeovrIton 2 G3RTE 1.385 Southgate RC 94 GW3MPB 745 Merthyr Tydfil ARC 11: : 'r GGG 333YGR CLH OPS 445435 ThamesDunstable Valley Downs ARTS RC 3 G3NO M 1.370 Stockport RS (A) 95 G3OVT 740 Stevenage & D ARS t. 435Echelford ARS 4 G3FJE 1.335 Shefford & D RS 06 JG3DNJ 730 Sutton & Cheam RS G3ZLO 425 Maidenhead & D ARC G3YMC/A 1.300 Bracknell ARS G3SOC 730 Leicester Coll ARS 188 -{G4CHH 425 Hornsea ARS G4ALG/A 1.300 Bracknell ARS 98 G3VVV 725 Edgware & 0 RS 119921 G a3MTE4LEzYji 7 425Glenrothes & D ARC GW30AY 1.300 Swansea ARS 55 _li G2AJB/A 710 Grimsby ARS 424 10 Ma ;I Torbayle ARSsh am RS 6 G3YDX 1.290 Southgate RC G3XII/A 710 Leyland Hundred ARG G3ROZ 1.265 Addisco be ARC G3JZ WA 705 RNARS Portsmouth 193 G3CMH 415 YeovrIARC 91G4FA M 1,265 Cray Valley m RS 101 G3N WR 705 Wirral ARS G4ELIN 400 RNARS H MS Belfast G4AEM 080V 1.265 Govt Comrns ARC (A) 705 Edgware & D RS 194 4G818 G4EXV 400 Catterick Garrison ARC 12 G4BUX 1.260 Stockport RS (A) 104 G4AUC/A 700 Bracknell ARS 400 Oxford & D ARS 13 G3XUD/A 1.255 White Rose RS 105 IG4G ME 695 Stourbridge ARS 197 G3c.j 397 Cheltenham ARA 14 G4CNY 1.250 Hereford ARS LG4IP 695 Stourbridge ARS G3FM W 385 Catterick Garrison ARC G3KTZ 1,240 Southgate RC 690 Leicester RS 198 -1-G3USE 385 Dunstable Downs RC " L G3SJJ 1.240 ARC of Nottingham 1074 G3HYHG4DC 690 Hornsea ARS 201 G3ZYJYSF 385 Southdown ARS 17 G3MCX 1,235 Surrey Radio CC GW3GRY 690 Conway Valley ARS f 03001 3705 sLehiecteisot,edr sR S0 Rs 18 G4E0K 1,230 RNARS H MS Belfast 685 Southdown ARS 110 4. 3 ,,,M HHGF 19 G3SSO 1.227 Govt Comms ARC (A) 585 Bracknell ARS 202 T-G3ZNU 370 Martlesham RS 20 G3.1E0 1,220 Thames Valley ARTS G2FNK 680 Echelford ARS 204 G3SNLI 365 Torbay ARS 21 G4BP0 1,190 Martlesham RS 112 G3VYV 680 Leyland Hundred ARG 205 G4A0L/A 360 Reading ARC 22 G3XTJ 1,165 Southgate RC G4CVN 680 Bracknell ARS 206 G4FKU 350 Torbay ARS 23 G4ALE 1.160 Addrscombe ARC G4DDX 680 Stevenage & D ARS G30 W0 345 Dover RC, SE Kent 24 G3SJX 1.155 Addiscombe ARC 675 Oxford SD ARS (YMCA) RC 116 -[ G3ZZR 25 G3PEK/A 1.150 Stockport RS (A) 675 Leicester RS 207 -{G4CVL 345 Echelford ARS 26 0601 1.137 Stourbridge ARS 118 cliG EvRTT 670 Grimsby ARS G4ECI 345 Stockport RS 27 G3BFP 1.135 Surrey Radio CC 119 G4FFD 664 Hereford ARS 210 G3MLO 340 Dover RC, SE Kent 20 G3JKF 1.120 Crawley ARC 650 Surrey Radio CC (YMCA) RC 120 G3FLIW G3WRA 1.120 Hereford ARS G4BNT 650 Grimsby ARS 211 G4FUU/A 337 Surrey Radio CC 122 G3VAA 645 Farnborough & D RS G 30 G3UFY 1115 Addiscombe ARC IG 8SM3LMH 325 Crawley Court ARG 31 G3ZWH 1.105 Maidstone YMCA ARS 123 G3SVL 640 Farnborough & O RS 212 G4FBES/A 325 White Rose RS 32 G3R WL 1,085 Southgate RC 124 G3AUU 630 Govt Com ms ARC (8) 325 Thames Valley Ains 33 G4BOU 1.080 Verulam ARC 625 °unstable Downs RC 215 G5CAX 315 Shefford & D RS G3HJF03HOX 625 Crawley Court ARG 34 s G3KKO 1.075 Echelford ARS 1 GG43AWG4CCX P R 310 RNARS Chatham G4C WH 1.075 Sutton & Cheam RS 1251G3RUG 625 Stockpon RS (B) 216 a 310 Cheltenham ARA 36 1 G3FYE 1.070 Stockport RS (Al 120 4 G4AXD 620 Maidstone YMCA ARS 310 Surrey Radio CC L G3TR 1.070 Crawley ARC GW3C W 620 Conway Valley ARS G4FYF 310 Surrey Radio CC 1- G3RPB 1.060 Manlesham RS 130 G3FVC 610 Maidenhead & D ARC IG2FWA 305 Cheltenham ARA 220 -LG4BRK/A 1,060 Bracknell ARC 131 G3KLX 607 Southdown ARS 1G3BFE 305 RNARS Plymouth

40 G4CDY 1,045 Addiscombe ARC 132 j G3FVA 605 South Manchester RC 222 -rG3WFV 295 ARC of Nottingham 41 GM3ZSP 1.035 Glenrothes & D ARC L G8SC 605 Southdown ARS -LGM4BR M 295 Glenrothes & D ARC 42 1 G3TNO/A 1.020 Horsham ARC G3AGF 600 Govt Comms ARC (B) IG3EUE 290 Surrey Radio CC LG4DRS 1.020 Shefford & D RS G3EJF 600 Catterick Garrison ARC G3MKG 290 Farnborough & D RS 134 224 44 G5BK/A 1,015 Cheltenham ARA 600 Clifton ARS G3PZP 290 RNARS H MS Belfast 45 G3VIP/A 1,000 Grimsby ARS GG3d4 KYG RC 600 Glenrothes & D ARC G3YSZ 290 Southdown ARS 46 G3YVR 995 Crawley ARC 585 Thames Valley ARTS JG4DHF/A 285 Grimsby ARS 228 47 G3ZSU/A 985 Maidstone YMCA ARS 585 West Kent ARS LGM3HUN 285 RNARS Rosyth 138 1 32A53 R 1,1°0 48 G3ORY 980 Leicester Coll ARS 585 Hereford ARS 230 G3BP M 280 Themes Valley ARTS 49 G3JFF 975 RNARS Portsmouth G3TWG 585 Maidenhead & D ARC (G4ARI 275 Leicester Coll ARS 231 50 G3ORH 970 Maidstone YMCA ARS 142 G3RDO 577 Crawley Court ARG -LGM4ELV 275 RNARS Faslane 51 G3LRS 960 Leicester RS G3ZXA 575 Echeltord ARS 233 G4GGV 270 Maidenhead S D ARC 52 G4ENA 955 Dunstable Downs RC 143 1. G4FRN 575 RNARS H MS Belles/ 234 GM4BAG 269 Kingsway Tech Coll RAC 53 G3KAF 950 Stockport RS (B) GM3U M 575 RNARS Rosyth 265 Wirral ARS 235 54 G4AAL 940 Bromsgrove & D ARC 146 G3WOK 569 Southdown ARS j-I.GG 3XEGUXS 265 Southdown ARS 55 G3SJ E 930 Edgware & D RS 147 G3AKF 567 Reading ARC IG3BLS 250 Oxford & D ARS 237 56 G6LX 925 Surrey Radio CC 565 Verulam ARC 148 _r G3LxpiAGW4FXF 1G3HRH 250 Crawley Court ARG J-G3TIR/A 920 Crawley ARC 565 Merthyr Tydfil ARC . 240 Govt Comms ARC (B) 57 [G3LGF LG4AZN 920 Oxford 8i OARS 150 GW3J1 560 Conway Valley ARS G3LVZ 240 Leicester Coll ARS 555 Bury RS 59 G3GRO 915 Crawley ARC 239 G3WYYG4BOF 240 Leyland Hundred ARG 240Hereford ARS G2FOS 905 Wirral ARS G3BRSG3OU /A. 555 Gerard Univ RS IG3JKS 905 Verulam ARC 1511G4B,J1J/A 555 Stockport RS (B) GM4CUZ 240 Kingsway Tech Coll RAC 62 G4CJU 890 Catterick Garrison ARC 154 G3JE1 552 Stourbridge & OARS 1G3JPX 235 RNARS Chatham 63 G3LCH 885 Sutton & Cheam RS 545 Cray Valley RS 244 G4FAS 235 Stockport RS (8) 64 G3ZBA 880 White Rose RS 166- C G43XELRYX 545 Reading ARC G4FTP • 235 Stockport RS (C) 65 G3LP 875 Cheltenham ARA 157 G4BEZ 540 Govt Commis ARC (B) IG3YCT/A 230 Leicester Coll ARS 247 66 G3TLK 870 Torbay ARS 520 Hornsea ARS LG4FOT 230 Bury RS G4FUPG4BHF 520 Horsham ARC G2MI 860 Cray Valley RS 1G3JJC 225 Cray Valley RS G3LEJ 860 Govt Corvino ARC (A) 1581G W3MOK 520 Conway Valley ARS G3UVS 225 RNARS Plymouth 249 G3MGL 860 Crawley ARC 515 Echelford ARS 225 Sutton & Cheam RS 67 I 161 G3MCK G04F DC 70 G3MZVJA 850 Govt Comms ARC (A) 515 West Kent ARS G4AD MGM3PF0 225 Glenrothes & D ARC 71 G3PSM 837 White Rose RS 163 G3ZKN 512 Cheltenham ARA 1G3VNG 205 RNARS Plymouth 72 f G3PSP 835 Edgware & D RS G3WSZ 510 White Rose RS 253 I "G444p,IF ET321HiyHR 0 205 Maidenhead & D ARC L G4C/XA 835 White Rose RS 164 {G4BJB 510 Bracknell ARS 205 Glenrothes & D ARC 74 G3IBB 830 Canenck Garrison ARC G3C WL 505 Sutton & Cheam RS 20d Bromsgrove & D ARC G3WGV 825 Reading ARC 166 1 G3TLI/A 505 Hornsea ARS 256 75 04E01 200 White Rose RS 1 G4DUT 825 Mardstone YMCA Ans GM4AGS 505 Kingsway Tech Coll RAC 258 195 Sutton & Cheam RS 77 G3LIK 820 RNARS Portsmouth r G 3H A L 500 °unstable Downs RC fi.GG43BFAECw 190 Yeovil ARC 259 78 G3HT1/A 810 Grimsby ARS 169 LG3JFH 500 Cheltenham ARA 190 Manlesham RS 171 G2DPO 487 Shefford & D RS G3S WC 800 Horsham ARC 261 G5BOR 187 Shelford & DRS G3WRCI 800 Hereford ARS 172 G3UJX 485 Wirral ARS 262 -r 3YXX/A 185 DoirmiRC CA ,)SRECKent 79 IG4DUS 800 Verulam ARC 173 G3TIK 480 Stevenage & CI ARS 82 G3RSD 795 Grimsby ARS 174 G3HKU 475 Leyland Hundred ARG G4ELD 185 Reading ARC 83 G3ED W 785 Yeovil ARC G3TZE 470 Martlesham RS 264 GW3YLZ 177 Conway Valley ARS 84 G3OGY 780 Crawley Court ARG 470 ARC of Nottingham 265 G4EGO 165 Dover RC, SE Kent G4ECY 85 i3YEE 770 White Rose RS 175i 470 RNARS Portsmouth (YMCA) RC fiG4BUO/A 765 Oxford Univ RS GG4F M 3NZXE 470 Kingsway Tech Coll RAC 266 IG2NG 160 Thames Valley ARTS 104DESW 765 Clifton ARS 179 { G3y4 G G FJA 465 Oxford Univ RS LG4CVT 160 RNARS Portsmouth 465 Stourbridge ARS G3GC 760 Edgware & D RS 268 G3DNX 155 Stockport AS (C) 88 I 181 G4DV W 460 ARC of Nottingham G4FIE 760 Leicester Coll ARS 269 G4FFVv 150 Stockpon RS (C) GW3IN W 760 Swansea ARS 18,_r G2D MR 455 Sutton & Cheam RS 270 /G3LHJ 145 Torbay ARS 91 G4EBK 755 Grimsby ARS L 03810 455 RNARS Portsmouth LG5BU W 145 Oxford Univ AS 92 G3SNN 752 Govt Comms ARC (A) 184 GM3KPD 450 RNARS Rosyth

528 RADIO COM MUNICATION June 1978 Poso Consign ScoreSociety 144MHz Single-operator 272 G3TMO 140 Farnborough & D RS Pwr Best 273 _rG48vA 130 RNARS HMS Beast Posen Cellsign Points OSOs CtRA OiP ds km -1.G4GFU 130 Maidstone YMCA ARS 1 G8KAAW 2,463 352 AM51 200 540 275 G4FOE 120 Bury RS 2 GBJAG/P 1.839 244 Y065 18 530 276 G4CZO 115 RNARS Chatham 3 GW4GTE 1.597 240 YN65 350 440 277 G4AFJ 100 ARC of Nottingham 4 G8100 1,411 151 AK12 250 625 278 G4801 85 RNARS HMS Belfast 5 G4FES 1.389 195 YKO4 200 725 1G4E0.1 80 Dover RC, SE Kent 6 G3NAO 1,248 236 Z134 100 480 279 (YMCA) RC 7 GI8KIA 1.147 87 X021 160 723 G4FYS 80 Yeovil ARC 8 G81.7_A 932 257 21.59 100 375 281 G3GYU 77 Bury RS 9 G2HIF 923 158 21.33 120 479 282 GM4FVO 72 RNARS Faslane 10 G8KWC 669 127 21.32 60 518 283 G3FWR 70 Surrey Radio CC 11 G4ERX 646 115 AL22 30 465 284 G2CLN 60 Bromsgrove 8i D ARC 12 GEINIFJ 588 133 2141 70 500 285 G3R8L 52 Bromsgrove & D ARC 13 GBNRP 577 125 ZL24 3 419 286 G3IFB 35 Gov* Comms ARC (B) 14 08101 566 110 Y146 80 529 287 G3TKO 30 RNARS HMS Bollan 15 G8NSL 537 103 YM59 50 525 J•G3WVJ 20 Echelford ARS 16 GBLVM 536 114 2M14 10 475 288 -1G4GNV 20 Yeovil ARC 17 G8NPM 524 112 AL33 40 430 290 G3XFW 15 Yeovil ARC 18 I G8KSS 447 87 Y1.38 3 420 291 G3NUO 5 Stockport RS (C) 1.. G8JVM/P 447 95 21.31 3 458 20 G8KPZ 408 125 AL52 60 498 2148 12 362 Thanks also to all participants for taking part, and for their comments 21 GBB1J 381 95 22 04001 343 102 2147 3 340 (these are always read with great interest), for without them [here 23 GBNXM/A 311 46 X1(56 14 400 would be no contest! The HF Contests Com mittee looks forward to 24 GBCUG 305 72 2158 8 375 hearing from them all again next year. 25 G8BJG 283 65 AL41 10 310 G3NKS 26 GBNOP/A 270 60 ZL71 5 273 27 G3FPK 265 27 2160 50 650 28 GW8NSF 200 45 XN59 12 437 29 COJEO 147 57 AL31 20 325 March 144/432MHz Contest results 30 GE1FAT/M 133 20 2139 12 360 31 GBNNJ 109 43 AL31 16 225 This somewhat experimental contest was enjoyed by most and it 32 GBOMI 91 25 2M71 12 180 brought a large postbag of comments and suggestions for rule changes. These have been discussed and it has been decided to run 144MHz Multi-operator another contest next year, bût with the following modifications to the Pwr Best No. of rules: (a) single-operator stations would have the choice of one six- Posn Consign Points OSOs ORA o/p dx ope hour or two three- hour breaks, times of these to be at their own 1 G3P1A/P 4.340 560 ZL33 400 702 4 discretion. (b) 144/432MHz multi-operator stations only, would be 2 G3PMH/A 3,855 506 AM21 400 575 4 permitted to run two stations concurrently using different callsigns. 3 GW3OXD/P 3.537 461 YM54 150 500 4 one on 144MHz and the other on 432MHz. It is hoped that these 4 G3UNU 3,191 480 zmo4 400 527 4 $ 0321G/A 3.101 360 AM27 400 680 5 changes will encourage more activity on both bands. 6 GW4GMO/P2.678 386 YLO5 150 570 3 Unfortunately conditions for the contest were not the best, so the 7 GW8CSA/P 2 574 389 YN7E 400 626 7 Continental activity was not fully appreciated. However, as can be seen 8 G3FKI/P 2.421 415 AL21 100 545 4 from the tables, the event generated a lot of activity on the 432 M Hz 9 G4ERP/P 2.258 374 21.01 200 505 6 band and this was thought to be advantageous in easing the CIRM on 10 G8LTA/P 2.113 370 2M24 80 300 4 the heavily used 144MHz band. 11 G4GTH/P 2,097 292 YK19 100 578 3 12 G6HH/P 1,668 258 AK03 10 490 11 Congratulations and certificates go to winners and runners up in 13 G8MZWP 1,619 287 2111 40 480 3 each section. 14 GEIBBC 1.450 344 ZL40 20 510 2 G4BfL 15 GU8NIS 1,401 150 YJ48 200 638 7 16 G3ERN 1 335 277 AL41 150 517 8 144/432MHz Single-operator 17 G8M WA/P 1.230 264 AL53 37 478 6 196 2M10 120 495 5 Poso Callsign Points Points Points OSOs OSOs ORA 18 040SP/A 1.220 121 YPOS 150 755 - Total 144 432 144 432 19 GM4B WT/P 1.145 1 G4ASR/P 4,886 1.311 3.575 231 115 YM47 20 G8KSP 1.105 246 AL41 80 545 3 2 G8GP 2.320 - 2.320 - 98 ZL50 21 G6U W 1.014 168 AM61 50 480 7 197 ZMO3 100 560 6 3 G3SPJ 2.172 752 1.420 138 65 AL41 22 G3281 976 4 G3LRP 2.055 - 2.055 - 65 ZN33 23 G8LWU 932 182 21V143 50 456 3 5 G3WHK 1,945 850 1.095 202 67 ZL49 24 G3LRS 889 194 2M25 400 370 - 6 G8HHI 1.543 418 1.125 74 53 2156 25 G3OHM 842 175 ZM41 300 480 5 7 G881S 1.320 185 1.135 29 49 AL43 26 G8NAT/P 828 153 ZM38 50 510 6 8 G5UM 1.195 - 1.195 - 53 211435 27 G4CLB 795 198 ZL38 60 505 4 9 G8CDL 915 400 515 90 34 2108 28 G8NlY 707 188 ZOO 300 462 3 100 Y1.48 250 560 2 10 G4E0V/P 788 268 520 44 18 Y054 29 G8K80 612 107 YN52 12 450 4 11 G4EEV 653 513 140 66 2058 30 GW4ARC $92 12 G8ART 570 5 565 1 31 ZM4E 31 G4EKT/A 487 88 2N4C 24 367 3 117 ZL57 40 354 2 13 G81WA 559 319 240 46 16 2N18 32 G4BRA/A 447 14 G4CGS 402 7 395 1 21 ZN11 33 G4DUR 82 28 Zola 11 290 3 15 G8FOL 267 87 180 25 14 YN38 16 G8CTT 190 _ 190 - 18 AL41 Listeners Contest results Poso Station Points Points Points ORA Total 144MHz 432M Hz 144/432MHz Multi-operator 1 RS15822 538 468 70 ZL40 Poso Cellsign Points Points Points OSOs OSO« ORA No. of 2 RS34310 386 371 15 2180 Total 144 432 144 432 ore 3 RS20323 127 127 - YN47 1 GW8BHH/P 7.733 3.653 4,080 414 111 YM44 5 Checklogs received from G3W0G. G4BXN. G3CRC/P. GD5DZ, 08,10K. G8LYH. 2 GW4ALE/P 5.068 1.423 3.645 205 101 YM75 8 G180JG. 3 G8KUC 5.026 2.856 2.170 378 54 AL56 3 4 G3VCP/P 4.761 3.421 1.340 429 42 AL45 5 G3LCH/P 4.153 1.573 2.580 245 95 ZN71 3 6 G6Y13/A 3 700 985 2715 158 77 YL.49 4 7 G3XZW/P 2,978 2.403 575 293 19 YKO5 4 70M Hz Open Contest rules 8 GE101-IM 2.450 105 2.345 21 86 ZM41 5 9 G3WTP/P 2,195 885 1.310 177 70 2M68 5 1900-2300/0700-1500g mt, 12-13 August 1978 10 GJ3DVC/P 2,006 1.401 605 141 13 YJ60 5 All entries and checklogs to: VHF Contests Committee. c/o Mr R. 11 G8AZA 1.907 1.162 745 140 25 2069 2 Taylor, G4BEL. 12 The Rampart. Haddenham, Cambs CB6 3ST. 12 G8HGN 1.716 341 1.375 93 65 AL31 3 The VHF Manager's Trophy will be awarded to the leading station. YN46 13 0301J1. 1.637 427 1,210 83 42 3 The following general rules, published in the January 1978 issue of 14 G3WKF/P 1.375 - 1,375 - 27 XK56 4 Radio Com munication, will apply: 1, 2, 3. 4a. 5a, 6a, 7a, B. 9a. 10a, 15 G8OGL 1,159 894 265 147 22 ZL47 2 16 G3AHD 1.139 889 250 139 20 YN46 9 11-22. 17 G4EEE 1,021 606 415 139 23 2155 3 Listeners' contest. Rules 1-3 will apply.

RA DIO CO M M U NICATIO N June 1978 529 3-5MHz Field Day 1978 rules 12. Address for entries. RSGB HF Contests Committee. c/o D. Thom, G3NKS, 37 Whittington Road, Cheltenham. Clos GL51 608, Members who enioy low -power contests are invited to take part in this England. year's 3-5MHz Field Day. 13. Closing date for receipt of logs. 1. The general rules for RSGB hf contests, published in the January Phone contest: 16 December 1978. 1978 issue of Radio Communication, will apply. C W contest: 2 January 1979. 2. Eligible entrants. RSGB members resident in the British Isles. A 14. A wards. The Thomas (G608) Memorial Trophy will be awarded maximum of two operators per station is allowed. to the leading British Isles entrant in the cw contest. Certificates will be 3. W hen. 0900gmt to 1600g mt. Sunday 16 July 1978. sent to the entrants placed first, second. and third. in the British Isles, 4. Contacts. CW (Al) only in the band 3.510-3.560MHz. European. and non-European sections of each contest. 5. Exchange. RST plus serial number starting at 001. location 15. Dispute. In the case of any dispute, the ruling of the Council of (defined by a place name), and county code (see p63 Radio the RSGB shall be final. Communication January 1978). 6. Scoring. Portable or mobile stations: 15 points per contact. RECEIVING SECTION Fixed stations: 5 points per contact Rules as transmitting section except as superseded below. 7. Power. The maximum power to the pa stage must not exceed 10W. 1. The general rules for RSGB hi receiving contests, published in the The power for all parts of the station must be derived from dry batteries, January 1978 issue of Radio Communication, will apply. accumulators, or "natural" sources (eg solar cells or wind generators). 2. Eligible entrants. British Isles: RSGB members only. The practice of float charging batteries from petrol or diesel generators Rest of world: All SWLs. is not permitted. Entrants must specify how the power input limit was 3. Scoring. (a) British Isles SWLs should only log overseas adhered to. especially when com mercial equipment capable of running stations in contact with British Isles stations. well in excess of 10W was used. European stations logged score five points, non- 8. Antenna. The maximum height must not exceed 35ft above European stations 15 points. ground level. (b) Overseas SWLs should only log British Isles 9. Logs. Column (5) to be headed "Callsign of operator". stations participating in the contest. European Column (6) to be headed "Location and county of station SWLs may claim five points per OSO logged. worked" non-European SWLs 15 points per OSO logged. 10. Address for entries. RSGB HE Contests Com mittee. c/o D 4. Bonus points. As transmitting section. Thom, G3NKS, 37 Whittington Road, Benhall, Cheltenham, Clos 5. Logs. Log sheets to be headed "date/gmt. callsign of station GL51 6DB. heard. RS(T) and number sent by station heard, callsign of station 11. Awards. The Houston-Fergus Trophy will be awarded to the being worked, bonus points, OSO points". NOT MORE THAN 20 entrant with the highest checked score. Certificates of merit will be sent (DSOs MADE BY ANY ONE BRITISH ISLES STATION MAY BE to the entrants placed second and third LOGGED, and the CALLSIGN OF THE STATION BEING WORKED MAY ONLY REPEAT ONCE IN EVERY SIX CONTACTS LOGGED. 6. Declaration. As transmitting section plus "I certify that 1 do not hold a transmitting licence". 7MHz Contests 1978 rules Licensed radio amateurs and SWLs throughout the world are invited to take part in the RSGB's 7MHz contests. Log and cover sheets may be obtained from RSGB. 35 Doughty Street, London. WC1N 2AE; UK members should enclose a large stamped, self-addressed envelope. SSB Field Day 1978 rules

TRANS MITTING SECTION 1. The general rules for RSGB ht contests, published in the January 1. The general rules for RSGB hf contests, published in the January 1978 issue of Radio Communication, will apply. 1978 issue of Radio Communication, will apply. 2. When. From 1500gmt Saturday 2 September toi500gmt Sunday3 2. Eligible entrants. British Isles; RSGB members only. September 1978 Rest of world: All licensed amateurs. 3. Eligible entrants. Any group of RSGB members resident in the 3. Periods. Phone: 1200gmt 21 October to 1200gmt 22 October. prefix zones G. GU, GJ. GD, GI, GM and GW. This is a multi-operator 1978. contest. CW: 1200gmt 4 November :to 1200gmt 5 November. 4. Operation. Must be from one portable station, not located in a 1978. permanent building and not using a mains supply. No equipment or 4. Sections. Single-operator only. antennas may be installed on the site prior to 24 hours before the start 5. Bands. Phone: 7'04 to 7.10MHz. of the contest. This does not apply to the storage of equipment. CW: 7.00 to 7.04MHz. 5. Contacts. SSB only in the 3.5. 7, 14. 21 and 28MHz bands. 6. Exchange. RS(T) plus serial number starting at 001. 6. Scoring. Each completed contact with Europe scores five points. 7. Scoring. (a) British Isles stations with: outside Europe 15 points. The total number of points on each band is European stations: 5 points per OSO. added to give a grand total. The total number of countries worked on Non-European stations: 15 points per aso. each band is added to give a grand total. The final score is the grand British Isles stations may not work each other for points, or bonus total of points multiplied by the grand total of countries. points. 7. Logs. Separate logs for each band are required, together with a (b) European stations with: check list showing the countries worked on each band. Points will be British Isles stations: 5 points per OSO. deducted for NOT complying with this rule. (c) Non-European stations with: 8. Entries.To be sent to RSGB H F Contests Committee, c/o J. BezleY, British Isles stations: 15 points per OSO. G3HCT, Brooklands, Ullenhall, Solihull, West Midlands 895 5NW. 8. Bonus points. (a) British Isles stations: 20 Points for each 9. Awards. Certificates will be awarded to the three highest-scoring different country worked (RSGB list applies) with VE. VK, W/A/N/K, groups, and to the leading check log from each continent. ZL and ZS call areas counting as countries for this purpose. 10. Would groups welcome the introduction of a separate section with (b) Overseas stations: 20 points for each different British Isles prefix restrictions to antennas and equipment along similar lines to National worked, ie G2, G3, G4, G5, G6. G8. GD2. GD3. G04. GD5. GD6, GD8, Field Day? GI2, GI3, GI4, GI5. GI6, GI8. GJ2, GJ3. GJ4. GJ5, GJ6, GJ8, GM2, GM3, GM4. GM5. GM6. GM8, GU2. GU3, GU4, GU5, GU6, GUS, G W2, GW3, GW4, GW5, GW6. GW8. The prefix GB will not count for bonus points. 9. Final score. OSO points plus bonus points. DF Qualifying Event Rugby 10. Logs. Log sheets to be headed: date/gmt, callsign of station Date: 18 June 1978. worked, RS(T) and number sent. RS(T) and number received, bonus Map: OS Sheet 152 150.000 series. Northampton and Milton points. OSO points. A summary sheet is required showing the Keynes. countries or prefixes worked. Assembly: 1300bst for start at 1320 bst 11. Declaration. Each log must be accompanied by the following Location: Bucknell Wood. ngr 658448. declaration, "t declare that my station was operated in accordance with Intending competitors requiring tea are asked to notify Mr D. E. the rules of the contest, and in accordance with the terms of my Newman, Haynes House, 78 High Street. Whittlebury, Towcester, licence". The declaration must be dated and signed. Northants NN12 8XJ (tel 0327 857 350) not later than 12 June,

530 RADIO COMMUNICATION June 1978 DF Qualifying Event Coventry be operating. Prizes worth £160 to be won, plus a star prize of an HW202 144MHz transceiver kit, kindly donated by Heath (Glos) Ltd. Date: 9 July 1978. All facilities of Longleat Park available to the family, with trade stands, Map: OS Sheet 151 1:50.000 series. Stratford-on-Avon. Assembly: 1300bst for start at 1320bst. and RSGB books available at rendezvous tent bookstall. Plenty of Location: Chesterton, 6miles SE of Warwick, ngr 355583. parking space adjacent to the new rally site, which is only a short walking distance from Longleat House. Details from G4FRG. Intending competitors requiring tea are asked to notify Mr G. Whenham, Lavernock, Chapel Street, Bishops ltchington, Leamington 9 July—Upton Radio Rally, Details from M. Monro, G8DLL, 127 Spa. Walks (tel 0926 612806) not later than 2 July. Monarch Drive. Worcester. tel Worcester 423276. 16 July —Hornsea ARS Mobile Rally, Hornsea School, Hornsea, North Humberside. Details from GU M DF Qualifying Event Dartford Heath 16 July—RAIBC Picnic, Broadlands, Romsey, Hants. Details from Date: 23 July 1978. G4CO M. Map: OS Sheet 188 1:50.000 series, Maidstone and the Weald of 23 July—Cornish Mobile Rally, Penweathers School, Truro. Details Kent from Harry Adcock, 1 Bowglas Close, Ludgvan, Penzance TR20 8H D. Assembly: 1300bst for start at 1320bst. 23 July—Anglia Mobile Rally, Stanway School. Winstree Road, Location: Unclassified road off the A227. opposite Shipbourne Colchester, 10am. Details from G4DKI, 0TH R, tel Colchester (0206) Church. ngr 594522. 67512. Intending competitors requiring tea are asked to notify Mr P. G. 30 July—Scarborough RS Mobile Rally. Scarborough Technical Wells, 25 St David's Road, Hextable, Swanley, Kent BR87RJ (tel 0322 College. Details from G3RTN. 62726) not later than 16 July. 6 August —RSGB National Mobile Rally, Woburn Abbey. 13 August—Derby Mobile Rally. 20 August—Preston ARS Mobile Rally. Walton-le-Dale County High School, Bamber Bridge. Preston (one mile from M6, junction 29). Talk•in on S22. Usual attractions including bring and buy stand. Plenty of free parking. Doors open at 11am. Details from G8KTM, 0TH R. 27 August—Torbay Mobile Rally, venue to be arranged. Details from G3U10, tel Newton Abbot 3025. Contests calendar 10 September—Stalybridge Festival Mobile Rally, Cheatham Park. 17-18 June Microwave (Rules in May issue) Stalybridge, Cheshire. To be held in conjunction with the Stalybridge 12S June OF Qualifying avent, Rugby (Details in June 1978 Festival. Details from G8KOP. QTHR. issue/ 10 September—Telford Mobile Rally, Town Centre Malls. Telford. 24-25 June Summer 1-8MHz (Rules in May issue/ Salop (approached via AS exit off M6, A442 from N and S. or M54 from 1-2 July VHF NFD and SWL (Rules in April issue) W). Free admission and free parking for 5,000 cars. Jointly organized by Telford & D ARS and Salop ARS, the rally attractions will include 9 July DF Qualifying Event, Coventry (Details in June issue) trade stands, exhibitions, -flea market" for private sales, licensed bar. refreshments and toilets, club stands; and a free coach ride to 16 July 3-5MHz FD (Rules in June issue) 23 July DF Qualifying Event, Dartford Heath (Details in lronbridge Open Air Museum, the largest of its kind in Europe. Further June issue) details from G8DI R. tel Shrewsbury 64273, or G3UKV, QTHR. 30 July 144MHz QRP (Rules in May issue) 17 September—Peterborough R&ES Mobile Rally, Walton Sehool. 6 August DF Qualifying Event, South Manchester Mountsteven Avenue, Peterborough. Details from G3EEL, QTHR, tel 12-13 August 70M Hz Open and SWL (Rules in June issue) 65423/62881. 20 August DF Qualifying Event. Slade 24 September—Harlow & OARS Mobile Rally, Netteswell Compre- 2-3 September SSB FD ( Rules in June issue) hensive School, Harlow. Details from G8FRG. 232 Pennymead. 2-3 September 144MHz Open and SWL Harlow tel 0279 32486. 10 September RSGB Region 1 VHF 1 October—Great Lumley Mobile Rally, Community Centre, Great 17 September DF Final. basingstoke Lumley, Tyne & Wear. Trade stands, etc. Details from G8JLQ, QTHR. October- November 432MHz Cumulative 7-8 October 432/1.296/2,304MHz 14-15 October 21/28MHz SSB (Rules in May issue) 21-22 October 7MHz SSB (Rules in June issue) 22 October 70M Hz Fixed 4-5 November 7MHz CW (Rules in June issue) 4-5 November 144MHz CW Special event stations 11-12 November 2nd 1-8MHz 3 December 144MHz Fixed G2N M, 24-25 June Chichester & DARC has organized a station to celebrate the 50th anniversary of Empire Broadcasting. GB3DTS, 8-9 July Mobile rallies calendar The Barking Radio & Electronics Society will be exhibiting at the Dagenham Town Show at Central Park, Wood Lane, Dagenham. In 10 June —Scottish Amateur Radio Mobile Rally. The Palace of Art addition to GB3DTS, my and AMSAT-UK, there will be extensive cctv Bellahouston Park. Glasgow. Details from GM4FD M. coverage of the continuous arena displays. Further details from N. 11 June —Elvaston Castle Mobile Rally. Elvaston Castle Country Park Dowsett, tel 01-594 6584. (five miles SE of Derby on 85010), from 11am. Talk-in stations G3EEO/P on 1-8MHz. G3ZBI/P on 144MHz fm 522, G8KGC/P on The following special callsigns will also be on the air during June. 432MHz fm SUB, S22, and GB3DY, the Derbyshire repeater, on H81U, will be available from 10am. Attractions include IBA Oracle demonstration, grand prize draw, lucky programme prize. RSGB book- 1-30 June GB3SF M Ryde. H MS Mercury. Longleat stall, local repeater groups' stand. childrens' rides and entertainment, 3 June GB3SHS Bolton tombola, road safety exhibits, ATC demonstration, gymnastics display. 9 June G B3STD St Dunstan's gas-filled balloons, many other sideshows and full catering facilities. I GB3S MR Scottish Mobile Rally Rally free, but local authority car parking fee of 25p. Further details GB3RCS Catterick 10 June From G4CTZ. 0TH R. tel Derby 71875. GB3VRC Potters Bar Carnival 18 June —Plymouth RC Mobile Rally. TAVR Centre. Lambhay Hill, I GB3VER St Albans The Hoe. Plymouth, Devon (near the Citadel). Details from G4EVVZ, 17 June GB3LAS Birmingham 18 June —RNARS Mobile ',tally, HMS Mercury, Petersfield. Hants. IGB3YCC York Details from G4DIU, tel Havant 79464. 18 June GB3RN H MS Mercury Mobile Rally 25 June —Longleat Mobile Rally. Longleat Park, Warminster, Wilts. GB3PCR Plymouth Rally starts at 10am, and Dain Evans, PhD, BSc, Fl M. G3R PE, RSGB 24 June GB3LE0 St Ives President, will be in attendance. 144 and 3-5MHz talk-in stations will 25 June GB3L MR Longleat Mobile Rally

RADIO COMMUNICATION June 1978 531 Roller coaster, mint unused cond, £5. Wanted: Quad Spider. G4CJY. CITH R. Tel 0494 30018. rmembers' ads Microwave Modules 144/432 varactor tripler, in good wkg order. with circuit diagram, £20 ono. Sentinel 144 converter, 2-4fVIHz if.. £10. G8JJE. QTHR. 45ft commercial tower. non-tiltable. Mt square at bottom tapering to 6in at top, £75. SAE for details, rotating gear may be available as extra. G3ION, QTHR. Tel Southampton (0703) 769 706. These subsidized flat-rate advertisements are accepted as a service to SEL teleprinter. type LO 133, with punch and reader. modern unit members of the RSGB. They must be submitted on the Members Ads similar to Creed 444, good clean cond, £45 ovno. Sentinel 2m order form printed in alternate issues of Radio Communication, or on a converter, 28-30MHz. £10. KW dummy load. as new, £10. Pawley, 37 postcard similarly laid out. Each must be accompanied by a recent Denison Road. Feltham. Middx. Tel 01-751 2262. Radio Communication wrapper addressed to the advertiser, as proof of Avometer. Model 9 Mk 4, good cond, with leads, less leather case. membership, and a remittance by postal order or cheque for 75p £65 ono. G3MA, QTHR. (stamps not accepted). They will not be acknowledged. Those not Drake TR4C. £380. R4C, £280. AC4 with MS4 £70. DC4, £55. Or clearly worded or punctuated will be returned. No correspondence offers. G4CH P, QTHR. Tel 0508 470365. concerning this service can be entered into. Yaesu FRDX400 amateur bands rx, 160 to 10m, WWV. cb, spare The closing date for each issue is the 1st of the preceding month, but valves. £130. Telford TC10 2m ssb and fm te. £75. Datong speech no guarantee of inclusion in a specific issue can be given. Valid clipper board, £12. SWRI 0 single meter swr bridge. £4. First two items advertisements not published in the issue following receipt will be held buyers inspect and collect. G8KAX, QTHR (Essex). over until the next issue. OR666 gen coy rx. fitted fm tuner, xtal calib, full manuals, best offer. Trade or business advertisements, even from members, will not be C828 1/10W mobile te/rx hb synthesizer, carrying case, nicads. all 2m accepted for Members' Ads but should be submitted as classified or in 1kHz steps. £150, or part exch C146, KP202 etc. G4GHO, 5 display advertisements in the usual way. Traders who are members Seymour Road. Broadfield, Crawley, Sussex. must enclose a signed declaration that the items for sale or wanted are FT101 Mk2, 160m, fan, 600Hz and MFJ filters, Holdings speech part of. or intended for, their own personal amateur station. clipper. Bauer paddle, Asahi power/swr bridge. G -whip Tribander, The RSGB reserves the right to refuse advertisements, and accepts 10m section and 160m. 80m and 40m coils, two whips, multimobile no responsibility for errors or omissions or for the quality of goods 40m coil and whip, offers? Chris Page, G4BUE. Tel Hassocks 2394 offered for sale. Advertisements may be edited or abbreviated as anytime. necessary. KW2000B, usu. manual, Datong rf clipper, cw filter. Shure 201 mic. £220. G4GOU. 64 Oaklands Lane. Smallford, St Albans, Herts. Tel Post to: ME MBERS' ADS. RSGB, 88 BROO MFIELD ROAD, 0727 52768. CHELMSFORD. ESSEX CM1 1SS. Liner 2, mains psu, preamp fitted, exc wkg order, any trial or sked. £115. G3MYY. OTHR (SW Essex). Tel 0277 821341. Do not post to RSGB HO or Advertising Representative FT1Olas new, fan, spare o/p valves, manual, 160m mod kit, unused battery lead, £265. 2m Pye linear, two 4CX250Bs. blower, peu, 300W p.e.p.. o/p potent, spare 4CX250B, £150. AR 88D. mint. £100. Hudson 50W fm 5ch base stn. £50. All gwo. G3UPB. Tel 089 425 3323 or 022 FOR SALE 870 474 evenings. Excellent dx/vhf C1TH. 400ft eel, overlooking Bristol Channel. Gel-cell unspillable lead/acid batteries with Gel electrolyte, size superior detached chalet bungalow, gas central heating. 2/3 beds, approx 7in by 4in by 2in. 6V 7.5Ah, three months old, as new, cost new large lounge, sep shack. 40ft tower: woodlands, golf course, riding (23+ ea, two available. offers. GM8JUY. QTHR. Tel 0236 21022 stables. M5 access nearby; £24,500. G5UG. QTHR. Tel Weston- (home). 0236 20111 extn 397 (office). super- Mare 25961. Clearance of late G2IM components: valves, resistors, fixed and KW200013, comp with peu, manual, Shure mic, spare valves. £175. variable capacitors, valve holders, meters, old type xtals. 8C221, etc. G3SQM. QTHR. Tel Hambleden 443. SAE for detailed list. R. Radford, 22 Bishops Avenue, Elstree, Herts. 2m Vagi. 14-el, as new, £16. Set 12 SAJ110 ic dividers. £6. Organ 432M Hz ssb transverter, MMT 432/28, £62. G3UBX, 0TH R. pedal contacts, set 30, £8. Xtals, HC6U, all kHz, 18940, 71103. 12025, "Rad com m" '73, '75, '76; SWM '75, '76; PW '73. '75, '76; 8525. 26025, 19025, 15677.5, 75p ea. G3LWT. QTHR. Tel Hunger. Constructor '75: E2 per year. B C221 P, mains, orig charts. manual. £20. ford (048 86) 3396. Buyers collect. G8KLI. Tel 021-472 4678. National Panasonic GX600. fm/lw/mw, bfo, df, antenna. Heathkit GR78 rx. 200kHz-30MHz continuous coy, good cond. timer, £50. MFJ ssb filter, £8. SSTV filter, £10. P. Barker, 11 Dipton £60. Wanted: AR88, must be in good cond. Paul Griggs. Tel Penn Gardens, Tunstall Estate. Sunderland SR3 IAN Tel Sunderland 3164. 226883. KW107 atu, new cond. few months use only, £95. Carr paid. GI3ZCK. K W 750 low pass filter, £7. Well-made mains psu, outputs 150V QTHR. Tel 0232 56221 ext 36, 9am to 5pm. stabilized, 300V and 1,250V, suit LG300, £15 ono. Modern naval Eddystone Edometer (gdo). Heath 58640 vfo, 6K8 65J7 metal morse key, "click stop" gap adjustment. key click filter, free standing, valves. Taylor, 8 Heythrop Drive, Middlesbrough. £7. G3J FC, 0TH R. Tel Crayford 522489. JVC radio tv cassette, as new; Murphy and Winthronics new radio Equipment of late G3UXN: Drake TR4 sideband tx/rx: AC4 psu; cassettes: small quantity new valves; Wien digital clock radio; Worlstar RV4 remote vfo: MN2000 antenna matching unit: Yaesu FT101 B multi-band radio, mint; all letters answered. L.D. Ireland. "Carnhell", sideband tx/rx; KW1000 linear amp: lcom TC215 144MHz tx/rx: Camborne. Cornwall. Tel Praze 236, anytime. Modular Electronics ME202/25 144MHz linear; RCA AR88D, orig Video monitor. Sin mono, s/state. 11in by Sin by 10in, mains, circuit, handbook: Heathkit SSB610 'scope unit; HRO rx, orig psu, six coils; etc, £40. Sony 9in tv TV9-306UB, mains or 1 2V, wkg (just), circuits. Panda PR120 cw/a.m. lx, all band atu; BC221 frequency meter, £15. Europa 2m transverter, 28MHz in, 6-40pa. £48. PSU for above, calibration cards, handbook: Coder AT5 lx. ac psu: Coder PR30 spkr, ex-KW2000, £30. Buyers collect. Tel 01-648 5895. anytime. 160/10 preselector; 60ft Versatower. crankup, 3-el Triband and 10-el Tandberg portable reel-to-reel tape recorder. PRO Reporters Model 144 beams; collection of radio equipment from 1920s or earlier; offers 2, 3-speed, mixing facilities, before and after monitoring, line-out etc, and enquiries to G3ABU, OTH R. Tel 08047 3401. c/w mic windshield and carrying case, as new, battery and in- Yaesu FRSOB and FL50B, 50W, ht, ssb, cw, a.m., tx 80-10m, rx structions. £60. T. Waller. Tel 0224 24715. 160-10m, xtal calibrator, both immac cond. hardly used, prefer buyer FR5013, £55. Marine rx 659/670. £20. Hartley oscilloscope, type 13A, collects. £150. G8FPB, QTHR. Tel Nottingham 301097. £20. Prinz Ti Super 8 movie camera. £20. Carr extra. Stewart, Vanguard. rf strip. 6-way xtal socket and switch, £4. Cambridge mic, GM8OKA. Tel 0290 21378. amp. a.m. squelch boards, audio o/p trans. £1. Xtals: 8.0625, £1.50; Liner 2, fitted preamp, exc cond, low spurious, has been successfully 8.03625. £1. Sig gen E692, circa 1936. charts, offers? Garrard SP25 used with 6-40A linear, £100. G8KGF, c/o 4 Cannon Street, Swindon Mk 4 pinth and cover. £15. P and p extra. G8DLT, QTHR. SN1 30D. Tel Swindon 2284, Monday-Friday 4-5pm only. Europa 13, 28/144, as new. £60. Sphinx cw/ssb lx (1964 CO WW 160 AR88, spkr, fm disc. £55. Panda Cub. much modded, cw only, £15. winner), control unit, £50. New 432MHz linear, Q0V03/20 fully TCS12 rx. £15. Creed 7B teleprinter. covers. £15. BC221, £16. CD568 ventilated screened rf unit, no psus. £30. Buyer collects or carr at cost. 'scope, needs attn. £10. LB Vanguard, control box, mobile mount, etc. G3G RL. QTHR. Tel Mansfield 20324. £20. Valve 2m converter. £4. Ex-radar 'scope. £5. Plessey stabilized ht FL200B tx. 240W pep., good wkg order, £100. Will deliver psu. £4. 19in by 5ft 6in rack, £4. Tape recorder, wkg, £4. 844 on 70-26, reasonable distance. G3VDY. "Glenfarg", Selside Road. Horton•in- £8. Prefer buyers collect. Wanted: KW2000A or similar. G4FUP, Ribblesdale, N Yorks BD24 ONT. QTHR. Tel Southwater 730575.

532 RADIO CO M MUNICATION June 1978 F460 uhf base stn, wkg cond. vgc. offers around £100. Standard Pye U450L uhf base stn, wkg cond. xtals on 433.2. £50 ono. Will C828M, 11 xtals, h/b psu, exc cond, little used. £145 ovno. Pye PF1 deliver locally. G8B0 M. QTHR. tx/rx, nicads. G8JWN. OTHR. Tel 0472 56362, after 1800 for details. FT101 10-80m, matching spkr. little used. C250. KW E-Zee For C828M ring G8NU W. Tel 0472 57717. after 1800. match/Asahi swr combo to suit, £25. Trio 2200G, mint. 5ch, nicads, G3PLX vdu kit, all ics and pcbs. incl ready-built KBD diode matrix, charger, etc, [100. G3WPX. OTHR. Tel 0380 86 259. also cursor kit, 7M Hi xtal. edge connectors. uhf video modulator, £60. FT101 E with 350Hz cw filter, hardware, etc. boxed, 10 months old, Twin meter swr son bridge, £6. Wilson 15m 4-el Vagi. £40. To be genuine reason for sale, £425 ono. Please ring G4GIM. Tel Worcester collected. GM3XN E, QTHR. Tel 0294 67326. (0905) 354727. evenings or weekends. Class D waverneter, int mains-driven psu. £10 ono. Quantity Europa B 2m transverter, £60. 2m Jaybeam, 6-el quad. £12. Technical Practical Wifeless and Electronics, '69 to '77, £5 ono. G8JED, 0TH R. Associates audio compressor, E12. Prefer buyers inspect and collect. Tel Paul, Lincoln 21159. G4CH K. QTHR. Tel Swindon (0793) 45269. Three-section lattice tower, approx 30ft total. £30 ono. High. M MV432 70cm tripler, £15. MMV1296 23cm triplet. £28. G3HB W band Pye Cambridge, comp with xtal, control unit, all cables, mic, wkg converter. 144-28MHz, £5. 70cm monitor re. using Pye Europa board, on a.m., £25 ono. G8K013. Tel Carterton 841741. (No callers please). mains/12V, RB4/SU8/R B14, circuit, £32. PM2-15 pa module. FT2FB 12ch 144MHz tx/rx, fully stalled with 11 simplex and R6, unboxed. £14. Wanted: TR3200G. 5XY12M. MMT144/28 transverter. f130. R7 xtals for FT2FB, £3. NR56144MHz monitor re. £40. G8LXY. MBM48/70. PMH2/70, Agee AR10. G4FRE, OTHR. OTHR. Liner 2. with PA-3 preamp, exc cond, little used, comp with mobile Shure 444 dynamic mic. high imp, data sheet. C10. G3GPB/A. Tel mount, h/book and orig packing, £105 ono. Carr by arrangement. 0293 33571. G3M0E. OTH R. Tel Cheltenham 24217. Pye Bantam, 3ch. £35. Stabilized psu for Bantam, £12. Hudson AM. TD224 rtty vdu, £150. Microwave Modules transverter, 70cm, 108, vgc, unmodified. handbook. £12. Codar PR3O. self. -powered. £6. 432-28-8, £100. Motorola D1 kit, full ram. £100. SVVTPC dual floppy Codar PR30, needs psu, £4. Truxox tape deck, spare capstan motor. discs with software, built and tested, £800. 4K ram, built and tested, £10. G3PCA, QTHR. Tel 01.478 3741. with sockets. £75. Barrel printer, with circuits, £75. G4DAW, OTHR. Slow-scan tv monitor. (45. G8CGE, 0TH R. Tel 01-656 5285. Tel Northampton 714821. anytime. Trio TS520, £320: FT101E, with 600Hz cw filter. £375: both mint CSE top-band comp a.m./cw stn, transistor te and re, spkr, mobile ant cond. Cooper, GM 3VMB. 17 Castlepark, Fairlie, Larga. Ayrshire. and mic, carrying box, instructions/circuit, wkg order, sell comp only, Icom IC22A, as new, in orig packing. toneburst, xtals SO, S20-24. R3- £40 ono. Buyer collects. G3THC, OTHR. Tel Milton Keynes (0908) 7, R7 rev, £135. Murata CFR 455H filter, £6. Feakes. Tel East Stoke 316730, evenings and weekends. (063 685) 230, evenings. Yaesu FT/FP200. all 10m, G3LLL clipper, pair new output valves, AR88 re. with S-meter, orig cond, new valves. manual, £80 or swop. manual. orig packing, E240 ono. Trio 2200GX, little used, 9ch. nicads, FR5OB rx, 160-10m, calib, manual, £65 or swop. Wanted: Datong FL1 case, manual, etc, £125 ono. Stolle 2010 rotator, f25. G3VSD. 2 Moss filter. J. P. Wright. 16 Headington Road, Earlsfield, SW18. Tel 01-946 Close, Helmshore, Rossendale, Lancs 894 4J0. 1570. evenings. Europa Band spare valves, mint, £65. Hudson 2m fm base stn. solid- KW2000, plus dc psu, £110. 829B with base, £5. Wanted: FT200, state rx, most popular channels. £50. AR30 rotator, brand-new, never FP200. G3UUU. Tel 0223 834411. used. £35. All plus corn, GU4C1-1Y. OTHR. Tel 0481 25815. TS700, unmodified, as new, orig packing, £300. G8GTY, 0TH R. Tel FRG7, E125: KW108 monitorscope. £45; Tech Assoc BP2 audio Chesterfield 36496. bandpass filter, £20: all items perfect, unmarked. G8WS. 0TH R. Tel Storno 600, boot mount. 12ch. 10 stalled, standard control box, full Maidenhead 23239. length leads. mic. xtal t/burst; second control box with full autoscan. Heath HW32A/HP13A, manuals. £85 ono. Creed 92 tape sender. lock in, lock out. etc, mic. xtal t/burst; exc cond. handbook. £155. manual, £12. Two multi-turn dials. £4. 10.7MHz filters, Buyer collects. Tel 01-648 5895. anytime. 44S/LQU/90113. f3 ea. Pye FM10, new, offers? All postage extra. CCTV transistorized camera c/w plug-in modules, 25mm Cosmicar G3LDI. OTHR. Tel Wymondham 603463. lens; metal cased 12in matching monitor: all professional built. c/w Europa. vg, int transmit/receive antenna relay with PL259 o/p socket, circuit sketches and leaflet: cernera fault. Buyer views and collects. spare pa valve, all leads, £55. Wanted: HW32(A), ac psu, in good cond. Offers. GM3VXR, OTHR. Tel Motherwell 65443. G4 BZE, QTHR. Tel Exeter 51646. Eddystone S770R, as new, with manual, £80 ono. G3A0Y. OTHR FR5OB ix. incl 160m, all 10m, plus 2m. xtal calibrator, exc cond. £80. (Lincs). Tel 0472 87268. Ayo AVT portable valve tester. B9 output socket. adaptor for 85 valves, Trio TR7010, extra eats. as new, boxed. £140. Trio TR7200G, SO. beautifully made, offers. GM3TBV, OTHR. Tel Blairgowrie 2520. S20. S21, S22. 532. R3. R4. R5. R6, R7. auto toneburst, vgc, boxed. FTDX401, little used, in mint cond, manual, spare valves, orig packing, £140. Wanted: (or exch) IC202, IC215. G4BL..I. QTHR. Tel Brighton a really top-class tx/rx, for only £285. G4EWG. 0TH R. Tel Constantine (0273) 503980. 588. Technical Associates re bandpass filter, C10. G4BMX, QTHR. Tel FR101S, 10m, comp. exch for FT221, etc. Wanted: TR2200GX and 045-388 3808. good oscilloscope. G3T BF. Tel 045 382 4853. FDK Quartz 16 fm mobile tx/rx, boxed, exc cond, fitted lOch. R3-R7. Trio TS0 510 tx/rx. remote vfo 5D. ac psu/spkr, cw filter fitted, recent SO, S20-523, toneburst. £120. G80KG, 0TH R. Tel 0632 482798. new pas and alignment by Lowe, exc cond, £185 ono. G3RDT. 0TH R. LG300, comp with two rf units. Labgear psu and modulator, remote Tel Chichester 87704. control, £35; RAI re, £25. AR88, spare valves and coils, part of manual HAC K Plus re, covers 9-170m, comp with batteries, spare valves, £30: all in going order. G2FMJ. QTHR. Tel Potters Bar 55960. cond as new, £12. VLF tuner, good cond. £6.50. Hayman. 66 New Good home wanted for a Liner 2. preamp, mobile mount. handbook, Road, Abbeywood, London SE2. Tel 01-310 7355. after 7pm. £100 ono. Also its' shack mate, IC22A, 11ch, fitted toneburst, mobile Liner 2 ssb tx/rx, psu. mobile mount, mic, exc cond. £115 ono. mount, handbook, £115. G8KKA, OTHR. Tel Midsomer Norton Morrison, 14 Woodcote Road, Tettenhall, Wolverhampton. Tel 0902 412874. 755634. Mosley Atlas vertical antenna, £18. Hi- Mond BK100 bug key, new. Yaesu FT2F13, 144.480, 144.500. 145-000, S20-524, RO, R5, £125. £8. Valves: 4/125A, two, E5 ea; TT22. £3. Collect or carr al cost_ Yaesu VC355D, 220M Hz counter. mains/12V. £120. Ferguson Courier Burgis, 11 Morningside Avenue, Portchester. Fareham, Hants. 12in portable tv, mains/battery. E40. G8FFI, OTHR. Tel Cosham Drake R4C. two extra filters, one year old, moderate use, marvellous 86184. rx, surplus to requirements, £390. G3REO. QTHR. Tel Coniston 329. Trio 9R59DS. £35; also Lafayette HE30. £15: both rxs in exc cond. FDK Multi 11 tx/rx, almost new, in box, B whip antenna, magnet G3EFC, 2 Hartland Road, Barrow-in-Furness, Cumbria LA14 4ER. mount, five months old, real bargain, £130 the lot. Mike Kushner, 19 QM70 Cobra transverter, 2m-70cm, hardly used, mint cond, £55. Malvern Drive, Stony Stratford, Milton Keynes. Tel Milton Keynes Xtals for SU8, (suit above with TR7200G or similar), E3. Hamgear 564547_ preselector, immac, £9. G4GTJ. Tel Burnley 36146. 150W a.m./cw Mini mitter Mercury tx. pair TT21 in final. 80-10m. Big shack clearance: PW '66-71. PE '65-74, RC '66-71, EE '71-75, int psu, in good order, £20. Wanted: 2C0 0-multiplier/loudspkr unit 20p ea plus large sae. Also many more incl TV, SWM. ET!. AM, WW, for Drake 2C rx. G4CH L. 0TH R. Tel Gravesend 68233. sae for details. Robin Bayley, 8 Field Lane, Kemberton, Nr Shifnal, FT200. FP200. KW atu. 1p filter. KW son load. mic, will split. £270 Salop TF11 9LR. ono. Buyer collects. GW8CNG, OTRA. FT200, FP200. £210. TS700. £270. G4DSC, OTHR. Tel 0765 2230. 18AVT/WB. £40. 6-el 2m Jaybeam, Stolle automatic rotator. 30It Collectors' items: old Pye Trimeasy battery sig gen type 94 631. aluminium pole, £45. 60kHz tuned whip, Rugby MSF. son. General 100kHz-25M Hz: QP240 valve: miniature early lin National Company Radio frequency meter and xtal calibrator 160kHz-60MHz. mint, £25. 'scope, 115V; 1924 Practical Electricians Pocket Book: three suitcases Fletcher, 62 Moorbridge Lane, Steeford. Nottingham N09 8GU Tel of early valves. some new: cash offers. G3MBL, OTHR. Tel 01-445 0602 397446, 4321.

RADIO CO M MUNICATION June 1 978 533 Eddystone EC10. fm demod. 2m converter; 20W 2m linear, 12V rf Two-bedroom semi-detached house, three years old, 600ft est, vox, suit IC202; 2m fm tx, ¡IA/ o/p. With xtals; 70cm tx/rx; G3TDZ 2m radio shack/garden shed. 6 miles GB3BC, 9 miles Cardiff, 12 miles rx. wkg pcb; offers. G8BAA, QTHR. Newport. easy access W Wales or Bristol. offers £11,000. Also Codar Eddystone 940 gc rx. late model, little used, various atus, the lot £160 AT5, mains psu, £15. GW4CJC, OTHR. Tel Caerphilly 860466. ono. Buyer collects. G81 X, OTRA. Tel 0782 24941. evenings. Microwave Modules converter, 144/28 lo, almost new, £15. SSM FT221 R. mint cond, still under guarantee, £325. GI4BTG. Tel 0231 70cm converter. 432/144. (13. Homebrew converter, 144/28. mosfet 52236. rf/mixer; pcb w/box. £3. post extra. Wanted: FT221R.G3AGX. OTHR. Tel Hull 822276. Cony Micro Mod 144MHz. 2-4 i.f., makers' checked. £12. Amex B W ANTED whip. new. £4. Jaybeam 5-el Yagi 144MHz. nearly new. £4. Viceroy Mk3 or 4. extra half lattice filter pref, also manual, state cond Telefunken phones, 'twenties, offers. Buyers collect antennas. G3ADK, and price, can collect 70 mile radius of Manchester. G3SNM. 113 0TH R. Tel Luton 27595. Town Lane, Denton, Manchester M34 2DF. Tel 061-320 8156. Drake R4C, mint, 160-10, £350. 2m AM25 mains lx, only £10. For the Wireless Museum: valve tester. Voight corner horn: pre- Mosley 10-20m vertical. £5. G3PBO. OTHR. Tel 021-373 2282. war valves; components: rxs: txs: books: catalogues: magazines; evenings. callbooks: loan of 30-line Baird Televisor. Collection arranged. Details Trio JR599 custom special, 160-2m. a.m./fm/cw/ssb. all filters, please to curator, G3KPO. 0TH R. Tel Shanklin 098 386 2586. handbook, in exc cond and wkg order. £160 ono. Chris Knight. 10 Codar PR3OX preselector; state price and cond. G2VF, 0TH R. Parkhill Road. Sidcup. Kent. Tel 01-300 0564. after 6pm. Reasonably-priced 19in rack mounting rxs, covering frequencies Pye FM100, pan converted 2m. many spares, £40. Codar AT5. mic, 15kHz to 30MHz; txs for amateur bands only: rxs for other amateur mains and mobile psu. £35. H/B 30MHz dfm with preamp, £30. Brass bands: setting up stn. Will collect S Scotland. J. C. Thomson. 38 morse key and audio oscillator, £5. Used 00V03/10s, 50p ea. Tel Admiralty Place. Beith, Ayrshire KA15 1JS. Tel Beith 2141. Andrew, Romford 28582. Racal TRA921, loan of full technical handbook and circuits. Colin Arac 102 rx, 2/10m rx. (65. Please write, all letters answered. P. H. Baker, 21 Grove Road, Luton LUI 10-1, Lovelock. Seale Hayne College. Newton Abbot, Devon. AM handheld or portable high band tx/rx, in reasonable cond. H. FR400SDX, all options, orig packing, in mint cond, £180. KW2000A, Mitchell. G4DYB, QTHR. Tel 440311 ext 72, Monday-Friday. very good cond, £150 ono. G4BVY, c/o G3UNU. QTHR. 7.30am-4pm. Drake R4B, T4XB. MS4. AC4, all xtals, filters, superb. £610. Valves: H01. reasonable cond; Bauer single paddle unit; Technical Associates 16 vhf pa, mostly new, £25. SW mags, '64-71, bound, £7. Pract rx bandpass filter. G4CEM. OTHR. Tel Hitchin 2990. Electronics and others, approx 100, £6. Wayne Kerr CT53 vhf sig gen. Webster mobile antenna coils for the Big K mobile antenna. £12. Buyers collect. G4AXS, OTHR. Tel Barham (Kent) 381. Hathaway. G3JHI. 0TH R. Tel 01 -720 2386. 2m and 4m Emsac 10W txs, a.m., frn. cw, both fitted 5 xtals and Versatower P60 or similar, rotator and three-band quad. G3UVZ, switched position for vfo. separate matching common mains psu, QTHR. Tel 01-778 4085, evenings. matching 4m nuvistor converter 28-30M Hz if., fb cond, circuit HRO type M. with glass valves and psu. G2VF, QTHR. Tel diagrams. £72 lot. G3UVS, QTHR. Tel 082285 2986 Southampton 775064. Standard C828, plus vfo, £150. Ridgway Watt 5-digit 50MHz Valves. type 813; also cheap 160m ix, KW160 or similar. Palmer, counter, £50. Deng rtty tiu with afsk, £40. Solartron CD523S 'scope, G4FMO, OTHR (Leics). Tel Ashby (05304) 3973. dc to 10MHz. handbook, £35. GBAEV 2m converter. £8. Buyers Ultra/Burndept Lion high-band a.m. 15W mobile info; especially collect. G4GRT. Tel Swanton Morley 580. coil details M5B8AB/10. For sale: three Pye AM257s, comp, wkg high FR506 rx, recent pro overhaul. exc cond, £80. Burns phase modulator band, offers? G8EZT. 0TH R. Tel 01-749 2584. with xtal. £6. Burns audio processor. (6. Burns psu. £5. (213V03/10, Collector seeks early radios, xtal sets. Osram Music Magnet 4 rx, used, 50p. Pye FM10D, part converted 2m. many spares. £40. AT5. Eddystone All World 2 rx. Eddystone four-pin coils, horn spkrs, Blue psu, £35. Tel Andrew. Romford 28582. Spot inductor dynamic spkr. bright emitter valves, components. KW Atlanta. just completed grand refit, all new valves, c/vv irt, £250. magazines, catalogues, books, circa 1922-1939. Norman Richardson, Plywood telescopic mast. 27ft, tripod base, £10. D43 Telequipment db 2 Edna Road. Maidstone, Kent. 'scope, £50. 15ft aluminium pole. ?Gin wall, £12; smaller ones. 75p per Heath SB600 or HS24 spkr, must be Heath spkr: Trio TX310; meter ft. G3LCS. OTHR. Tel 0908 313379. movement, model 425. Taylor 83C or old meter, good movement. For TS820 digital, £615; Shure 444 mic, £15; SWR twin meter, £5: all sale: Emsac CN3 4m 28-30, with factory-built psu. offers? GI6VU. immac. Two 1,000V dc var capacitors (one split-stator), new and QTHR. unused: also G -whips. Robinson, G2KF. QTHR. Tel 072 681 2337. "Rad Corn" back issues, Jan *72 to Feb'78. G3SRZ, 30 Fore Street. New Zaerix 6BA6. 6BE6, 25p ea. Used NKT404, 25p ea. SN7476, St Blazey, Cornwall. Tel Par 3375. believed ok. 10p ea. Stentorian 10W 10in spkr. multitap 4/8/150. External crash limiter assembly. DLR headphones (two-pin £4.50. Mixed bag of transistors. contains ten various types. 50p. plug). 12V battery connector lead, for R209 Mk2; Canadian 52 set G4GHB, OTHR. tx/rx, wkg, unmodified, comp all connectors, etc; any parts for Redifon FT200. hb psu. (200. FT75, ac and dc psus, vfo FV50B, many xtal chs, GR410 tx/rx. G3UCT. Tel Fleet (02514) 6998. £200 ono. EC10 Mkt. ¡mi. £50 ono. CR100, £25. Electroniques hb EC80 or 604 valves, up to ten. EIRS12959, 4 Branksome Hill Road, coil pack, psu. etc. £25. G3ZJY. OTHR. Tel 0385 66773. Bournemouth. Barlow Wadley XCR30. ac psu. £130 ono: consider part exch any AR77E manual, loan or buy. G8NMX. QTHR. Tel 061-485 8760. good 2m fm rig. Giv13LVG, 0TH R. Tel Cumbernauld 20850. Blower for push pull 4CX250Bs, size important, please let me have Starphone M5, uhf, mobile, 5ch, xtalled SU20, RB6. R B10. auto dimensions in first instance.G8FEQ, 0TH R. toneburst. £95. G3USB. Tel Sheffield 890970. Oscilloscope. bandwidth 5M Hz, prefer dual beam, will collect within Liner 2. fitted preamp, good cond. £95. S0306, £1.50. 280 50 miles. Ian Rhodes. Tel Dronfield (Nr Sheffield) 418790, after 6pm. cpu+ P10+ ctc (unused), £29. Motorola 6800 02 kit (assembled), Heathkit S810 sideband adaptor with handbook, for DX100U tx, extra memory and buffers, £175. MC1458CP1 (dual 741) op amps, prefer factory-assembled unit G4GX0, 6 Longsight Lane, Cheadle 25p ea. G8AJB. OTRA. Hulme, Cheshire SK8 6PW. Pye Vanguard FM25B. 60W o/p, fitted 10 pos Ledex, preamp, I/b Vibroplex bug; 840 ix. For Sale:Zenith Photo Sniper outfit; or exch. 145-00 S20, S21. 522. S23, S24. R5. R7, comp with mic. control box. GW4ANO. QTHR. Tel Abersoch 2675. cable, boot cradle, manual. £85. Teleprinter rx terminal, £5. Delivered TV Regonda b/w 6in VL100, case red, must be mint cond. your price SE England. G8ISX, W WI. Tel Orpington 29586. paid if right, will collect but must be within reasonable distance. Paul Power unit, 13.8V stabilized, 7-5A, electronic overload cut-out, for Allen, 19 Wright Close, Wheathampsiead. Nr St Albans, Herts. Tel running mobile rig at base, £12. Tel Sevenoaks (0732) 62481. Wheathampstead 3688. Marine vhf r/t, 25kHz channels, ITT STR20B, 12/24V dc, 10W. 4CX10004, with base and chimney, and suitable ht tranny. Also any comp with manual handset, channel xtals, £140. carr paid. Racal other ORO components for linear on board ship, 10, 20m mobile linear. Mobical u/I 10.7MHz ssb filters, carrier xtal, £8 pair. G3JMJ, OTHR. Webster bandspanner, 10m walkie-talkie or mobile rig. Jenkins, 22 Tel 073 271 863467. Foulden Road. Stoke Newington, London N16. Trio TS900. spkr/psu. dc-dc-ac converter, super rig, custom built, Help! Overseas member wants to obtain Fisk Solariscope (propg'n very little use, two spare pa valves, unmarked, as new, orig packing predictor). Please write VK3APN, 78 Dovvnshire Road, Elsternwick, cases, £400. G4BVQ. Tel 061-236 5866. Victoria, Australia 3185. Pye FM25B ORO 2m tx/rx. QQV06404 in pa, 10 sets of xtals, S20. Medium heavy duty rotator. 40-60ft telescopic lattice mast, S21, S22, S23, SO, R5. 116. R7. rev R5. rev 117. wkd eight countries FV101 B. hf mobile tx/rx. G3VDN. QTHR. Tel Billesdon (053 755) 636. while mobile, £48. G3VLW. QTHR (Berks). Tel 0635 62973. BC221 frequency meter. psu, calibration manual. Karagianis, 20 Lea Scanning rx. 7ch Heath GR1I 0, designed for marine band, will work Road. Sonning Common, Oxon RG4 9LJ. Tel Kidmore End 2085. on 2m, 12V dc, 110V ac, £50. G8IBV, OTRA. Tel 0452 36119. Heathkit 0S2 'scope in fb cond, plus handbook. G3LOL, QTHR.

534 RADIO CO M MUNICATIO N June 1978 STEPHENS-JAMES LTD G3MICN

47 WARRINGTON ROAD, LEIGH, LANCS 1NN7 3EA TEL 0942-676790

TRIO New Selecta De Luxe Range WESTERN TS820 HF Transceiver .. £645.00 Selecta 1 m mast section.. £9.56 Western Towers and Antennas now available DG1 Digital read out option .. £127.00 Selecta 18 mast section extension • M OO TS520S HF Transceiver .. £489.00 Selecta 10-15-20m head £14.65 TECHNICAL ASSOCIATES TS700S VHF Transceiver .. £542.00 Selecta coils for LF £6.25 We are now ammo as sole distributors for the full TS700G VHF Transceiver .. £426.00 SXR30 range of Technical Associates equipment TR7500 VHF FM Transceiver .. £225.00 New model solid state receiver RX Band Pass filter . . £29.75 TR7200G VHF FM Transceiver . •£189.00 550K1-12 to 30MHz . £142.75 RX Peak and Notch tiller . £29.75 TR7010 VHF SSS Transceiver .. £189.00 Audio Compressor . £28.75 TR2000GX FM Portable Transceiver .. £139.00 MICRO WAVE MODULES Peasetector M K1 with relay £29.75 TR3200 70cm FM Portable Transceiver £182.00 Transveners Preselector MK2 for SWL £26.55 TR8300 70cm UHF/FM Transceiver .. £227.00 MMT432/28-S. £133.88 Crystal Calibrator . . £21.85 PS5 Power Supply Unit £58.00 MMT432/144-R £169.88 These prices include VAT and postage MMT144/28 SP70 Speaker .. . £18.00 £88.88 New models available later in year Converters DMI300 G.D.O. Absorption Wavemeter £45.36 SAE with all general enquiries please. C01303G Monitorscope . £129.00 MM C144 any IF £20.25 All crystals and accessories available. MMC144/28 LO £22.50 SWL TUNING UNITS AT200 Antenna Tuner £82.55 MMC70/any IF £20.25 MK1 Cover 2-30MHz . £17.50 MMC70/28 LO £22.50 MK2 Covers 550KHz to 30MHz £23.00 YAESU MMA144 Preamp £14.133 Designed and manufactured by us. Fifty switch. MMC432 any IF £27.00 FRG7 Solid state receiver £177.00 able tunable positions, will match any antenna to MMC1296 any IF £28.00 FRIO1D Receiver.. £489.37 your receiver. Now in use in over 40 countries Frea m ag/ose ers FL210013 Linear amplifier .£313.87 Price includes VAT and postage on these items• £85.32 SECONDHAND EQUIP MENT JAYBEA M Atlas 210X with Deluxe Mobile DRAKE 4Y/4M 4 metre 4 element Beam . £12.65 SSR•1 Solid state receiver .. £150.00 CS-2M Glass-fibre coliner . £30.93 Mount £375.00 8Y/2M 8 element Yagi . £10.00 Belcom Liner 2 Transceiver £100.00 6Y/2M 5 Element Yaw . . £7.71 STE MILAN Drake T4XC Transmitter with AC psu £425.00 P8M10/2m 10 element Parabeam . £25.35 AR10 26-30MHz AM•SSB Receiver P8M14/2m 14 element Parabeam . £311.43 Drake RAC Receiver with 2 Filters £450.00 module .. £39.50 AA1 Audio amplifier for ARIO. . £4.75 Full range of antennas for 144MHz. 70cm avail. Eddystone ECIOMK2 Receiver £100.00 M OO able with full range of tubing, clamps, etc SEND AD4 FM Discriminator • . - Eddystone EC10MK2 Receiver £110.00 AR20 FM Crystal controlled SAE for full details. KW2000E Transceiver £295.00 receiver module . £50.00 BARLO W WAD LEV AT23 FM Crystal controlled transmitter £50.00 XCR -30 Rn £150 Magnum 2 Mk2 Ttansvenet £100.00 AGIO Tone burst unit .. . . £4.50 XCR-30 FM Rs £170 Magnum 2 Mkt Transvener £65.00 ALES 10 watt Linear amplifier . £27.00 MARC SSM Europa Transvener £55.00 ARAC 102 2 band Receiver . £100.00 NR56V 2m FM Receiver 12V dc £54.00 ARAC 170 70cm and 10m Receiver . £127.00 Yaesu FT200 Transceiver £275.00 ASAP Stabilised 21 amp power unit . £27.50 F.D.K. Yaesu FT10IE Transceiver £400.00 4840 40 wart Mobile FM amplifier . £55.00 TM56B VHF Monitor Receiver £85.00 Yaesu FL101 Transmitter . £240.00 AK20 VHF/FM Transceiver . . £160.00 Trio OR656 Receive! £80.00 STATION ACCESSORIES TEK Single Meter SWR Wall type £9.50 Trio TR200GX Transceiver.. £110.00 NEW RANGE 10-80 Trapped dipole 2kW PEP. Single Meter ,5WR Desk type £9.80 Trio TR7200G Transceiver . £120.00 Complete. not a kit £50.00 £10.80 Twin Meter SWR Desk type KWO' Multiplier £16.00 3 way Antenna Switch .. £5.50 ROTATORS 6 way Antenna Switch £16.50 KW2000E Transceiver £300.00 AR40 £51.57 KPR400 £97.00 Bauer Single Paddle Unit £10.95 Coder CR70A Receiver £25.00 CD44 £106.87 AR22R £48.38 Junkers Morse Key . £29.76 HAM2 £145.12 Samson ETM-3C C-Mos Keyer . £63.88 Shop Hours Mon to Fri 9.30am to 5.30pm Katsumi Electronic Keyer . £60.75 Saturday 9.30am to 5pm G-Whip Mobile antenna range STE Electronic Keyer £106.00 ACCESS and Barclaycard facilities. Tribander helical 10-15-20m . £19.75 NyeKing 001 Morse Key . £6.76 HP terms arranged Part exchanges always wel- LF Coils for iribander £5.91 NyeKing 002 Morse Key.. • £7.81 come. Good clean equipment bought for cash. Telescopic for coils £2.25 Nvelfing 003 Morse Key.. £8.43 Items sold on a commission basis Basemoum standard £3.38 Hy-Mound Morse Key .. £8.76 We are located on the A574 Turn at the Grey- Basemoum swivel type .. £4.45 Drake TV3300 Low Pass Filter £18.00 hound Motel on the 4580 (East Lanes Road) and Flexiwhip basic 10m £11.25 HP3A Low Pass Filter . . £2.95 we are about 4• mile on right. No parking problems Coils for flex i £5.91 Plastic Antenna Insulators 20p at any time

SPECIAL OFFER. CA3089E, £1.50; 2N3866. 80p ; 2N3553. £1.00; 40673, 60p: 2N5180 30p: 3N201. 60p. 2m 12V FM TX board Phase modulator Buying a second-hand rig? 5kHz deviation max Size: 140mm x 82rrim x 23mm. HC25/U Crystal Multiplication X12 Sent for evaluation, P&P 30p. 12V 1W £20. 2N4427. The RSGB has just published a useful list of nearly 200 70p; CA3001. £1.50; 2N5913, £1.50; 2N5945 (4W. 8dB). £8.00; 2N5946. £11.00: 2N5541. £4.00; 0083. 20p; 40964. £1.40; 40965. £1.50; equipments. comprising receivers, transceivers and transmit- 2N3375, £2.00; 0C202, 10p; PT3500. £1.20; BLY33, £1.80; 2N5590, ters, which gives brief details of each and includes a survey of £5.00: 2N5591. £8.00: 2N3632, £3.00: 2N6080. £4.50: 2N6081. £5.50: the com mercial equipment scene during the past 40 years. Just 2N6082. £8.00; 2N6083. £9.00: 2N6084. £12.00; 2N5642. £8.00; the thing to have handy when scanning Me mbers' Ads! 2N5643, £11.00; BYF50. 20p; BC108. 10p: BC183L. 10p: BLW39. £3.00; 2N3478. 40p: 3N202, 90p: MPF102. 40p: 40841. 50p; 13C1674. 10p: BSY90, 30p: 2N3904. 10p; 2N3906, 10p; Integrated Circuits: CA3007. 43pages £1.71 incl p&p £1.00: CA3014. 80p; CA3018, 70p; CA3023. 80p; MC1550G. 50p; MC1496G. £2.00: CA3000. £1.00: SL620/30C. £2.00; MC1741CG. 80p; 2N3819. 20p: 2N2270. 40p: BLY55. £2.00; Transmitter tuning capacitor W e nearly forgot to mention -with every list comes the 79pF, £1.00: S0239 sockets. 50p: N socket to BNC socket adaptor. £2.50: N rest of the new 17th edition of A Guide to Amateur Radio socket to N plug. £2.00; N plug to N socket. £2.00: HC25/U crystal sockets (another 115; pages) cunningly attached at no extra cost. pcb. 15p; Minimum order £1.00. Mail order only. P&P 20p How's that for value t HELLER ELECTRONICS 49 Blossom Waye, Hounslow. Middx.. 11N5 9H8

RADIO COMMUNICATION June 1978 535 YAESU proudly announces a new synthesised 2m FM transceiver \e/ YAESU FT-227R

The world-famous Yaesu state-of-the-art technique has brought computer theory into VHF communications.

Wh a t are the frequency splits for repeaters? Don't worry! Yaesu has computerized it. In addition to a conventional ±600kHz split, any transmitter offset frequency is memorised with a touch of a push- button.

IN h a t was my last frequency channel ? Don't check! A touch of a push-button will bring you back to the memorized channel instantly.

Why only one knob to select a channel out of 800 channels? Yaesu utilises a -OPTICAL COUPLING" system to select each channel in 10kHz steps and the channel may be offset 5kHz higher with a touch of a push-button. Thus 800 fully synthesized channels are provided with one knob and no rotary switches to get oxidized and noisy.

Why wait? the FT-227R is on your dealer's shelf now.

Many, many other features such as automatic encoder-decoder for tone guarded squelch (TGS) (optional). Tone burst accessed repeater operation, automatic final protection, busy channel indicator, ,high - low output selection, diecast front panel, and famous Yaesu quality throughout I

And all at a most attractive price. See your dealer today for an informative catalogue.

Amateur Electronics, South Midlands Com munications Ltd, 508-514 Alum Rock Road, S.M. House, Osborne Road, Alum Rock, Totton, Near Southampton, Birmingham B8 3HX Hampshire SO4 4DN

536 RADIO COM MUNICATION June 1978 YAESU proudly announces

1980's RADIO TODAY: \e/YAESU The FT-901D M HF Transceiver

The Ham's dream —to have the best—is now Memory circuitry allows you to store a frequency, reality. then recall it with the push of a button for control of transmit, receive, or transceive frequency. Digital plus analog frequency readout. PLL frequency Advanced receiver features include rejection tun- derivation. ing, dual-filter variable-bandwidth IF passband tuning, and audio peak frequency tuning for sharp CW reception. Unparalleled receiver selectivity is VOX, calibrator, noise blanker, RF speech pro- yours. cessor. and 20d8 attenuator are all built in, not expensive accessories.

Built- in Curtis 8043 IC Keyer I Provides reliable operation and superb immunity from RF Modern computer-type plug -in circuit boards for interference. quick servicing and clean layout.

Famous Yaesu quality workmanship throughout. Toroidal output circuitry and RF negative feedback The FT-901 DM will be available soon. See your for maximum reliability and purity of emissions. dealer for a colour brochure on the FT-901 DM and Rugged GE 61468 final tubes. other Yaesu products.

Amateur Electronics. South Midlands Com munications Ltd, 508-514 Alum Rock Road. S.M. House, Osborne Road, Alum Rock, Totton, Near Southampton, Birmingham B8 3HX Hampshire SO4 4DN

RADIO COM MUNICATION June 1978 537 ELECTRONIC 2 ALEXANDER DRIVE, HES WALL, WIRRAL, MERSEYSIDE. L61 6XT Tel: 051-342 4443 (4.30-7.00pm) P. SERVICES Gables CRYSTAL. BIRKENHEAD. Telex: 627371 VAT-PRICES EXCLUDE VAT, WHICH SHOULD BE ADDED AT THE HIGHER RATE (121%) FOR ITEMS MARKED (H) AND AT THE LOWER RATE (8%) FOR ITEMS MARKED (L)-OVERSEAS ORDERS (Inc. Eire e nd Channel Isle!) NO VAT CHARGEABLE. 2M TX Er RX CRYSTAL AVAILABILITY Et PRICE CHART CRYSTALS FOR THE NEW BRITISH 70C M CHANNELS We are stocking the following channels R80 (434-60/432-00). RB2 CRYSTAL (434•66/433.05), RB4 (434 70/433-10). R B6(434.75/433-15). SUB (433-20). RB10 (434 85/433.25). R814 (434-95/433-35). SUIS (433-45) and SU20 FREQUENCY -... (433-50)-TX and RX for use with: PYE UHF Westminster (W15U). UHF RANGE ,...... Cambridge (U10B), Pocketfone (PF1) and STORNO COL/COM 662 all at £2.36 USE(TX or . . C x plus VAT (H). For the U450L Base Station we have the TX crystals for all the aboya and HOLDEE. channels plus the RX crystals for SUB at £2.36 plus VAT (H) The RX crystals for.

iX•HC6/U iX•HC6/U , RB2. RB4. RB5. RBIO. R014. SU18 and SU20 for use in the U450L Base Station, OUTPUT e 2 together with the TX and RX crystals for the remaining SU channels (SU12- › ni 52MHeRNSC25/U 52MHeRNSC25/U I 8MP1/.TX,11C25/U 4MHz 25/U Er 8MP1/.TX,11C25/U I 44N1H2FIX.HC25/U 41foUirMliC6 6Mlir TX HC25/U HC25/U TX fil(FIC6/U 6Mlir 5MHETKFIC6/U IGMHe 44MHbRXHC6/U FREQUENCY 25/11 fi 11MHeRMIC6/U 36MtikT)(FIC5 433.30- R TTY. SU16-433-40 and SU22-43355) for all the aboya equipments are available at £3.20 plus VAT (H) delivery as per class (b) 2m items. 144-030 b b b b b b b b 144.4/433-2 a b c b o b b b 4m CRYSTALS FOR 70-26MHz-HC6/U 144 480 b b b b b 1 b b b TX 8.7825MHz and RX 29.7800MHz .. at £2.36 each + VAT (H) 144 800 b b b b b b b b RX 6-7466MHz at £2.90 each + VAT (H) 144 850 b b b b bi b b b 10.246MHz "ALTERNATIVE" I.F. CRYSTALS-£2.36 -I. VAT (H). For use in 145-000/SO a a a Pye and other equipment with 10.7MHz and 455kHz I.F.s to get rid of the "bircly" 145-050/R2T a b a iust above 145-0MHz. In HC6/U. HC18/U and HC25/U. 145 075/R3T a b a CRYSTAL SOCKETS -HC8/U. HC13/U and HC26/U (Low loss) 16p each 145.100/R4T a b a VAT (H) A- lop P. Er P. per order (P. Et P. free if ordered with crysials). 145 125/R51 b a a CONVERTER/TRANSVERTER CRYSTALS -HC1B/U 145-150/R6T b a a All at £3.00 + VAT (H). 38-6666MHz (14-4/28). 42MHz (70/28). 58MHz 145 175/R7T a b a I (144/28). 70Mhz (144/4). 71MHz (144/2). 95MHz (342/52). 96MHz 145-200/R8T a a a a a (1,296/432 144), 101MHz (432/28), 10t 50MHz (434/28). 105•6666Mhz 145-300/512 b b b b b b b b (1.296/28) and 116MHz (144/28) 145-350/S14 b b ' c c C c C b 145 400/516 b b b b b b b b CRYSTALS SPECIALLY MANUFACTURED FOR AMATEUR USE 145 500/S20 a a a a a a a TO CUSTO M ERS REQUIRE MENTS 145.525/S21 a a c a 0 d a a Now supplied to our new Improved amateur specification (temp_ tol. ±3Oppm 145.550/522 a a c a a a 8 a 0-60"C. adj. toi. ±30oom) as follows: in HC6U 1.5MHz £3.95 + VAT (H) and 145.575/S23 a a c a a a a a HC6/U 2-105MHz and HC 18/U and HC25/U 4-105MHz £3.36 + VAT (H). Delivery usually 4.6 weeks. Please give circuit conditions (L.E. Load in pf etc.) wsem s era-array-au o- o- W crocroc, crocroc, W o- o- 145.600/S24 aera-array-au a s wsem c a a a a a 145.650/R2R b b b b a b a a when ordering. Fundamentals (1521MHz) will be supplied. Io 30pf circuit 145.675/R3R b b b b a b a a conditions, and overtones (21-105MHz) to series resonant conditions unless

7 0"0".. W Cab a+ an CI,. w w

145-775/R7R b b cr b b a b a a 1MHz and 5MHz in HC6/U and 10MHz and 10.7MHz in HC6/U, HC25/U. £2.80 pe 145.800/R8R 8 a a a a a a a + VAT (L).

1.45.95 a b w w b b b a b b b BURNS ELECTRONICS Prices: (a) £2.36. (b) and (G) £3.20 t VAT (H). We are the Northern Appointed Agents for BURNS KITS etc and can supply AVAILABILITY: (a) and (c) stock items. norma ly available by return we have many of their products from stock over 5.000 items in stock). (b) Four weeks normally but st is quite possible we M ODULAR COM MUNICATIONS SYSTEMS could be able Io supply from stock N.B. Frequencies as listed above but in For the RTTY enthusiast we can recommend and supply the "MCS" range of alternative holders and/or non-stock loads are available as per code (b). products. This includes terminal units. AFS keyers. magnet drivers for TTL ORDERING. When ordering please quote (1) Crystal frequency. (2) Holder. (3) interface, telegraph distortion measuring adaptor. RTTY audio processor, power Circuit conditions (load in pf ). If you cannot give these, please give make and units, etc. etc. For the CW man we have the "MCS" CVV filter which give three model al equipment and channel or output frequency required and we will advise if stages of active filtering. Please send S.A.E. for full details of die "MCS" range we have details. JAPANESE AND AMERICAN EQUIP MENTS ANZAC M0-108 DOUBLE BALANCED MIXER With the ever increasing popularity of Japanese equipments we have further 6-500Mhz supplied with full details for only £5-95 plus VAT (L). expanded our range al stock crystals We can now supply for YAESU FT2F. F2F2FT. Ft2 Auto. FT224). most of the ICO M range and the TRIO- KEN WOOD CRYSTALS FOR PROFESSIONAL USE range. We can also supply from stock crystals for the HEATHKIT HW202 and HW17A CRYSTALS TO COM MERCIAL SPECIFICATIONS YAESU FT221 CRYSTALS NOW IN STOCK, ALL AT £2.96 + VAT (H) All We can supplycrystals to most commercial and M IL specificetions, with an express popular channels-For repeater use advise xtal frequency required as earlier service for that urgent order. Please send S.A.E. for details or telephone between models have different shift mals to later F1221 P. We can also supply the crystal to 4.30-7pm and ask for Mr. Norcliffe. give NORMAL -tune to RX - working (as FT221R). For 70cm we can supply the 1.6MHz shift xtal for direct use with a MICRO WAVE MODULES MMT432/144 TEA MS: CASH WITH ORDER - MAIL ORDER ONLY-S.A.E. WITH ALL which we can supply loi £161 .00 -I- VAT (H). SPECIAL OFFER: If ordered with ENQUIRIES-'PRICES INCLUDE P. Et P. (BRITISH ISLES) EXCEPT W HERE STATED -OVERSEAS CHARGED AT COST. transverter 70cm shift Crystal FREE!!

RACAL M A197B SELECTOR-PR OTECTOR.Power 100/250 G2DY M ANTI-TVI TRAP DIPOLES AC. Rangel M/c -30 M/cs in 6 bands. Used condition £35. With new metal case £15 extra. Carr. £10. CUT OUT TVI TX-ing and SWL-ing, MODELS: CO M M UNICATIO NS RECEIVER RACAL RA.117E. Fre- SWL, £29.81; 500 Watt or SWL, £41.06 quency Range 1-30 MHz in 30Bands 1MHz wide. Effective Scale Length 145ft 6 in corresponds toi00KC/s. Power 100-125 or 200 2KW, £46.68; all complete inc. 75' feeder. 250 a.c. Internal Speaker. Crystal Filter. Bandwidth 100Hz to Aerial Matching Unit 500 Watt & S.W.L. 10-160 13kHz in six bands. with S-Meter. Two IF stages. Slow Motion BFO. uses 27 valves (BG7 and BG9). As new condition. with metres inc. Shipping Band, £16.25, handbook and circuit (in metal louvred case) £300.00. (Carriage 2KW Model £22.50 approx £10).All our sets are bought direct from the Govt. All are bench tested and checked in our own workshop before despatch, Inc. VAT & p&p Send 10" x 7" 1.2-p s.a.e. and for full Calibration. Send SAE only for any enquiries. Trade terms on 3x 9p stamps for details, aerial article, test quantities. Working demonstration on Ritty etc. in our works by reports, testimonials. appointment. JOHNS RADIO 424 Bradford Rd, Batley, LAMB DA, WHITE BALL, Yorks. Tel: 0924-478159 (9.30 am - 1 pm) W ELLINGTON, SO MERSET

538 RADIO COMMUNICATION June 1978 7,5-2•7rellt7,71109F91.!I MIDI ffle: 4 LEE ELECTRONICS LTD ESTABLISHED FOR MORE THAN TWO DECADES 01.723 6521 400 EDG WARE ROAD. PADDINGTON. W2 Telex: 298765 OPEN MONDAY TO SATURDAY LONDON'S LARGEST STOCKISTS OF YAESU • ANTENNA SPECIALISTS • STANDARD • ICO M • EIANTEX • JAYBEA M • REVCO • CM470 *ATLAS • ETC FRG-7 -DIGITAL DISPLAY Yes. The world famous FRG•7 is now available with digital read-out lined by Lee Electronics in place ol kHz dial . .. Special Price £190 • VAT For customers who already own FRG •7's we can supply the digital read out complete with installation instructions . . . . £37.00 +VAT FRG • 7 Digital £190 .. .. FRG-7 with analogue dial £164.00 FRG-7 DIGITAL £180 ERG '7 Perspex cover as illustrated £3.50 All plus 12}96 VAT

YAESU MUSEN PRICES (ALL AVAILABLE FOR IMMEDIATE DELIVERY) FT301 1/AX 1 8-30 100W FRG7 Digital £190 FRIO1SD Digital Readout TC500J 500MHz Counter 12V £490 FT221R 2m. "All mode" £357 £453.50 10 PPM £151 FT301D Digital Readout '301 (585 FT227 10W, 400ch mobile. FRI OIDD Digital readout TC601 Dig. Display 101 FV301 External VFO £75.50 digital £191 £541.00 & 401 £113 FP301 PSU/speaker C90 FT223 T/RX 2m. FM23ch FT101E Transceiver £485.00 Y0301 Monitor scope £155 50 FT2008 1/AX 3.5-30 £285 12V £139.50 FL101 T.X. 1.8•30MHz 230V £386.00 YO100 Monitor 2 tone osc £145 FP200B AC PSU/Speaker £65.50 FRIO1D DeLuxe "S" BC. FL2100B Linear 1 .2kW PIP £295.00 SIG8OR 1/AX. 2m FM FRG7 RX-5-30 cont. AC/Dc £164 FM £465 FT101 EE 1/AX 1.8-30 80x 25kHz 12V £195 AC/DC £469.00 ALL VAT 14% EXCEPT MONITOR SCOPE, CLOCK, COUNTER. WATTMETER, -• 8% MICRO WAVE MODULES DESPATCHED TO ANY PART OF THE WORLD POST FREE M MT144/28 Transvener £79 FREQUENCY COUNTERS CONVERTERS ATV435/51 convener £24 £62 MMC1296 converter 28 or M MT432/28 Transverter £97 MMD 050/50MHz counter MMC70. 4rn convener £18 M MT432/285 with Oscar MMI3 050/500MHz counter £79 144MHz IF £2 shift £119 Divide by 10 prescaler. 500p £25 MMC70/LO. 4m convener £20 All 2m converters can be supplied M MT432/144 Transvener £133 MMC144. 2m convener £18 with IF outputs of 2-4-12-14- M MT432/144R with 1.6MHz 18--28MHz 70cm models with IF shift £151 VARACTORS MMC144/L0 2m converter £20 outputs of 28 -14.-18- or 144MHz MMP12/3 Power supply 12V. MMV 1296. 23cm varactor £33 MMC432. 70cm converter £24 3A stabilized £50 ALL MICRO WAVE MODELS SUBJECT TO VAT IN UK 8% ON FREQUENCY COUNTERS. ALL OTHER MODELS 14%

A.S.P. MOBILE AND BASE STATION ANTENNAS Special of fer A.S.P. A680 U.K. Asp201 lw 2m mobile £3.25 Asp393 lw 3dB 2m mobile £17 Asp E462 70cm 3dB mobile £7.23 6dB 144/148MHz Co-linear Asp2009 a 3dB 2m mobile £5.95 Asp no hole boot mount £3.70 Asp E667 70cm 3c113 mobile £16.90 Power handling 350W. Length Asp629 w 3dB 2rn mobile £7.60 Asp magnetic mount £8.95 Asp A659 UK 70cm approx. 1211. List £51 special Asp677 j 3dB 2m mobile £13.50 Asp cutter clip less cable £3.85 5d8. base antenna £19.00 oiler £41.50 PLUS VAT 8% PLUS CARRIAGE

COM RANGE ICO M ACCESSORIES F.D.K. RANGE STANDARD RANGE C215 2m Bch £139 Exials S21 or S22 £4.50 pr. Multi Ul f U111 70cm mobile £221 C146 2M Hand held C215 2m 'Kroh (lined 6 ER Case 202/215 £6.67 Multi 11.2m mobile £184 with carry case, tone repeaters plus 4 simplex) £144 Mobile Bracket 202/215 £10.23 Multi 2700 Fm/ssb. Tx/rx £435 lersi. S20 and S22 £119.95 C202 2m SSB £152 Helical Antenna £3.25, p & p 25p New Mobile Master HELICAL ANTENNAS C22A IOW mobile £145 2W input 10W output £39.50 2m with 13 BNC £3.85 each C240 10W mobile £169.10 Base Master £19.50 KYOCUTO DIGITAL MODFL 2015 2rn with ph 259 £3.85 each C245E 10W FM/SSS £352 Mobile adaptor £4.95 IOW mobile 400ch Tx/ri £245 2m for IC215. C2I 1 E IOW FM/SSS £470 Helical antenna £5.50 Trio 2200 Ga. standard Small charger £5.25 J-BEA M ANTENNAS Cl 46A £3.25 C8600 10W Mobile £115.00 All transceivers +14% VAT ALL MODELS IN STOCK All+ post 25p. +12}% VAT C830S Marine H/Held £145.00 SPECIAL OFFER. Constant current Ni -Cad chargers Adiustable charge rate for AA or C type Ni -Cads Ideal for C202/215. C146A. Trio. etc. Price £8.35 + 8% VAT. p & p 50p

2m IOW Mobile with scanning m 70 40W Line+avr elpez £48.20 ALPHA W63 channels Fitted 9 channels £139.95 VAT 12e%

YAESU FT227R WITH LEE ELECTRONICS AUTO-SCAN

YES WE CAN NO W SUPPLY THE FT227R WITH AUTO-SCAN FACILITIES, DESIGNED AND MANUFACTURED EXCLUSIVELY FOR US -N OTE THESE STAR. FEATURES

* Scans 40 channels * 2 speed scan rate * Locks out unwanted channels * Auto matic tone burst for repeater operation * Reverse repeater facility * Scans between 145-146 M Hz in 25kc/s steps * Scanning facility

Controlled by switch lilted to microphone (not illustrated)

PRICE £231 PLUS VAT

RADIO COMMUNICATION June 1978 539 o -6 250 Hz dB !50- YAESU Ft TRIO -20 CW OPS

-30 BEAT the ORM!

Fit brand new purpose designed 250 Hz 8 pole filters and get the -40 best. Specially sharp resonse for superior DX and contest performance but not too narrow for regular OSOs. -so Easily mount on the pre-drilled FT-101, FR-101, FT-301, TS-520, TS-820 PCBs in your rig. No alignment For any rig listed £25.50 plus 124% VAT. Also available in the North from Holdings Ltd.. 39/41 Mincing required. Lane, Blackburn.

-6o 750 OTHER STOCK FILTERS: Inclusive of appropriate carrier crystals 8545. 8998:5. 9001 and 9001-5 KHz. Centre Frequency MHz 9:0 9-0 80 80 10-7 10.7 214 Hz Poles 6 8 5 8 8 e Use SSB Tx SSB TxRx CW FM AM/FM AM/FM max Passband KHz:dB 2-5:-6 2:4:-6 0-5:-6 12:-6 Ae58/:-F3m 15:-3 15 -3 Stopband KHz:d8 5-0:-60 4.3:-60 2:2:-60 21.6:-60 17-5:--70 35:-70 50.-80 Ultimate Attn. dB 60 100 90 90 90 90 80 Termination Ohms/pF 5001130 500/30 500//30 12001130 910//25 9101125 9101115 -80 [ Price. add 12e, VAT £20.60 £24.00 £22.50 £24.00 £24.00 £24.00 £25.20

INTERFACE QUARTZ DEVICES LTD., 29 Market St., Cre wkerne, So merset, TA18 7JU. Tel (0460) 74433. Telex 46283 inface g

Prices quoted in- HARRY COLLINS clusive of VAT. Cal- lers welco med by ST. TE R E S A S, EL Y RO A D, RADIO TIME appointment. Cash W ATERBEA CH, CA MBRID GE with order. Postage S I - I • T ELE P H O N E (0223) 860555 and Carriage extra. • Electrolytic capacitors. 1000pF. Assorted Boards, With capacitors, I L _I I • 16V. 10p each, 64pF. 100V, 35p each, resistors, transistors. etc (Useful for Complete digital clock/timer/alarm units from National Semiconductor, 16 & 32pF, 3501/, 50p each. 900pF, Spares.) with NO RFI problems. Both types 24 hour alarm format, fast/slow setting 100V, High grade screw terminals 35p Cathodeon Crystals Ovens, HC6/V, each. and direct drive LEO displays. Switched alarm outputs for radio etc. 26p each. 10 at £2. MA1012 0.5" bright LED display. 12hr format with PM indication • P.C. Board Pots. 250r, 330R. 5k. 10k. Vidicon Scan Coils (P-ye LYNX). 68k. 10p each Brand New. £2 each with bases. .7x1.4x3" space required behind panel £9.451 Monitor Cathode Ray Tubes, M38. Colvern Wirewound Multiturn MA1023 0.7" LED display. Switched 12/24 hr display, "on-chip" alarm 100WA/S, £10 each. Pots, 5000 Linear. 30p each. buzzer. 0.5x1.5x3.25 space required behind panel £11.251 Base Station Receivers, Type 30. £7 5 Henry Chokes, 600M/A, £4 each. 2201240v AC mains transformer £1.65 either type. State module number. each Relays Various 4 at £1. Two MA1012+ transformers: £20.00 - two MA1023+ transfo's. £22.50 Colour Television Monitor Scan Jack Field Plugs and Sockets. 20p Radio Component Innovation from AMBIT international Coils. Type M38 £1 each. Pair. Self-return Toggle Switches, 10p Vanner Synchronise Motors. 240V As well as being foremost with the worthwhile new ideas in components each, 50c/s. £1 each. and applications, our new '78 catalogue contains details of our new range Pan and Tilt Controls (Inc. 20-way flat ribbon cable, 40p/m of low cost meters with a wide range of scales, passive components that 4 micro-switches), £1 each. 30w vehicle mounting PA spea- are selected for semiconductor circuits, with standardization of pin and Phillips Fluorescent Tubes. 6' 4W kers, brand new. 15 ohms. £15 lead spacings for ease of design; ferrite beads baluns, torroids, coils, and Pi-Pin 50p each, 21" 13W Pi-Pin, el UHF bases, F27 type with T/T £75 filters for AM/FM/N8FM/SSI3 - including new low cost ceramic ladder each. Limited quantity 50 ohms to long wire filters from only £1.25 for 455kHz/12kHz BW. PriBattery Chargers. 12-way. £1 5. Ae. matching units 3-8MHz £8 each We will also introduce you a mats ot new devices, including the L200 nenlawatl Controls, Miniature 100k ON/OFF Assorted cable. PaChae IC voltage/current regulator. Output voltage adtustable from 3 ro 30y, with Sw..15p each: 500k ON/OFF Sw.. 10P current and thermal shutdown. Up to 1 8Amps output! CI.951. The TDA10133, a each. one IC com munications receiver, with balanced mixer. IF, multimode detector and 800m W cl Audio in one 16 OIL • only E1.95. The TDA1062 VHF front end m an IC. With RF(13alanced mixer, oscillator. IF output and PIN diode AGC drive Good to 201:1MH;, works down to DC, and only £1.95 i A Mato range ol DIY push button modulai switches, up to 10 way, 8pole You must Marconi DEV Meter TF7 910 £90 get a copy of the catalogue to see what's new in wireless Dawe DC VVM Type 611A £40 Catalogue and supplements 459 (incl. All prices exclude VAT, which is Marconi VVM TF1100 £40 12.5% except where marked 1 (8%). Postage and packing 259 per order Marconi VVM TF1041 £40 linc VAT). Single Sided P/C Board. Double Sided P/C Board, VI sq.ft or price or, ambit international 0 quantity, or cul lo order 2 Gresham Road, Brentwood. Essex. tel (0277) 216029

540 RA DIO CO M M U NICATIO N June 1978 S.E.M P.O. BOX 6, CASTLETO WN, ISLE OF MAN Tel. Port Marown (0624) 85277 A SELECTION OF OUR EQUIP MENT

£14-00 + VAT = £15.75 with Belling Lee sockets. For S0239 sockets add £1 .50+ VAT =£1.69. IN STOCK.

THE SENTINEL STANDARD 2 METRE PRE-A MPLIFIER The same circuit as above, but without the rf switching. Price: £8-75+ VAT = £9.85. IN STOCK. These pre-amplifiers are in stock for Marine Band and Satellite Band. Other frequencies to order.

PA3 2 METRE PRE-A MPLIFIER Size is only about 1 cubic inch. to fit inside your transceiver. Price £5-57+ VAT = £6.27. IN STOCK.

HF PRE-A MPLIFIERS Now that 15 and 10 metres are opening up, these pre-amplifiers are really coming into their own. Compensating for the drop in receiver gain on these bands. Used with a short aerial, they make a very effective ACTIVE AERIAL. They are wideband 1-40M Hz. 15dB gain.

THE SENTINEL AUTO HF PRE-A MPLIFIER With a change over relay which is operated by your transceiver relay for direct connection in your aerial co-ax. Price: £10.50 + VAT = £11-81. IN STOCK.

THE SENTINEL STANDARD HF PRE-A MPLIFIER OUR GEAR WILL BE AVAILABLE AT THE MAJOR Same circuit as above, less relay. Price: £8.00 + VAT = £9.00. IN RALLIES FRO M: — STOCK. The Amateur Radio Shop, Huddersfield (Northern These prices are for Belling Lee sockets. For S0239 sockets add Rallies) Waters & Stanton (South) Reg Ward & Co. £1.50+ VAT = £1.89.

Ltd (West). THE SENTINEL 2 METRE POWER AMPLIFIER AND PRE- AMPLIFIER EUROPA C HIGH POWER 2 METRE TRANSVERTER The power amplifier provides 40 watts output when driven by a 10 Quote from a letter received recently -it is nice to see how the watts transceiver. The pre-amplifier is the same as our Seminal convenience features have been added. It really is a very nice little Auto 2 metre pre-amplifier. It contains an rf operated switch with a unit and it turns the FT101 into about the most versatile unit you delay for SSB and operates on all modes. could hope to get your hands on -. This was used with a -L W' FM Sockets are S0239. Price: £53.00 +VAT = £59.62. adaptor to give all modes. We also have a 2 watt in, 12 watt out version. The "convenience feature" refers to the HF aerial socket on the All these are IN STOCK. Europa C which switches straight through to the transceiver when the Europa is switched off and giving no "plugging - change over S.E.M. Z MATCH between HF and 2 metres. Very popular and versatile little unit. Handles 15-5000 Ohms. Power 200W input—Drive 200M W —NF 2dB—Gain 30dB. Corn- BALANCED or UNBALANCED. S0239 and 4mm terminals for co- plete to plug into Yaesu equipment. Price: £00.00 + VAT ax or wire feeders. And rated up to 1kW. Price: =f11250. Ex stock. £34.50+ VAT = £36.85. IN STOCK. CPS10 Power supply—Dummy load attenuator for use with other equipment. Price: £50.00 + VAT = £56.25 Ex stock. SENTINEL DUAL GATE MOSFET 2 METRE

Automatic repeater shift (600kHz) is an extra £12-00+ CONVERTERS —Price £18.00 4 VAT £20.25. VAT = £13.50. SENTINEL X DUAL GATE MOSFET 2 METRE CONVERTERS Price £22.00 VAT = £24.75 PRE-A MPLIFIERS SEM 70 70CMS TO 2 METRE FET CONVERTER Price £18.00 -The best pre-amp—bar none." -It makes MP a readable signal -i- VAT = £20.25 from nothing." -It has removed the holes out of my journey to SENTINEL 70 70CMS TO 10 METRE FET CONVERTER Price work." "I now have a choice of four repeaters instead of one." £20.00 4 VAT - £22.50 Comments like these substantiate our belief that our pre-amps SENTINEL TOP BAND CONVERTER—Price £18.00 • VAT -- provide the best value for money. £20.25 THE SENTINEL AUTO 2 METRE PRE-A MPLIFIER For more details on any of our equipment. please ring or write New rf switching circuit gives greater sensitivity—faster switching. 12-months guarantee. Circuits etc supplied. adequate delay for SSB. Completely compatible with all modes. To order: C.W.O. or credit card. Just phone your credit Connect straight into your transceiver aerial co-ax and the rf relay card number for same day service. Prices are post paid for looks after the switching. Power rating is 100 watts. Prices: delivery in UK. We will probably be closed for T.T. week. First week in June.

RADIO CO M MUNICATION June 1978 541 SSB or FM 144 MHz Amplifier

The result of two years development and improvement. THREE additional features to the proven EDL 144. 1. A switch to change the operating conditions of the PA (Class C or AB2). 2. A miniature press button to simplify the setting of PA standing current. 3. Fan cooling as an optional extra.

£128-1-V.A.T. at/12.5% 432MHz Amplifier EDL 432 (50 Watts output)—E50+ VAT at 12.5% or as self-contained unit EDL 432p (50 Watts output) £135+ VAT at 12.5%. Polar Electronic Developments Ltd, Domville Road, Liverpool, L13 4AT Tel: 051-220 6666 s.

YOU OWE YOUR RIG CB ELECTRONICS G3LRB A GOOD ANTENNA! The World-famous JOYSTICK VFA (Variable Frequency Antenna) UNIT 3, 771 OR MS KIR K ROA D, PE M BE R T O N SYSTE MS continue to prove their worth in many amateur stations WI G A N W N5 8AT Phone Wigan (0942) 216567 world wide and in Government com munication. Tunes continuously 0.5130.00MHz and cari be installed in any location Comes in easily assembled form. carriage paid, 12;% VAT included Glo wing testi-. THE BEST IN THE NO RT H- WE ST monials from many users on our files. The people with a wealth of technical experience and SYSTEM 'A' 250w. P.E.P. OR for the S WL £36.00 kno w-ho w relating to amateur radio techniques, requirements and servicing, who will always be pleased SYSTEM 500w. P.E.P (improved '0' on receive) £42.60 to advise and assist in all respects whether it be sales, service or information. PARTRIDGE SUPER PACKAGES HO W TO FIN D US Complete Radio Stations for any Location All Packages feature the World Record Joystick Aerial (Sytem 'A'), From M6 Junction 26 follow signs for Wigan A577. At first with 8ft feeder, all necessary cables. matching com munication traffic light (T junction) turn right towards Wigan At next headphones. Delivery Securicor our risk. ASSE MBLED IN SE- traffic lights you are there BUT turn left, then 10 yards turn CONDS! BIG CASH SAVINGS! right BY CO-OP (Telephone kiosk) and shop is slightly to your right. Plenty of parking space Distance from motorway ; PACKAGE No. 1. As above with R.300 FIX. mile. SAVE £17.28! £210.55 PACKAGE No. 2. is offered with the FRG7 RX From Wigan follow A577 for Skelmersdale to traffic lights at SAVE C12.21 I £195.00 Pemberton (Ye Olde White Swan Hotel on your left). Turn right then 10 yards and right again by telephone kiosk. Distance PACKAGE No. 3 Hero is a lower •price. from Wigan 2; miles. Closed Wednesday high-quality package, featuring the LOWE SRX30. with all the Partridge extras. SAVE £12.21 I £177.00

AT LIST PRICES MICRO WAVE MODULES RECEIVERS ONLY, inclusive delivery etc. YAESU ANTENNA SPECIALISTS UNIDEN R.300 £184.50 FRG7 £162.00 SRX30 £146.25 ELECTRONIC DEVELOP- S.C.S. LINEARS AND PREA MPS For further details. send 9p stamp MENTS EMOTATOR ROTATORS You can phono our Access or Barclaycard number. ring 0843 62535 J BEA M LTD. lest 9) (or 62839 after office hours ) HY GAIN CD.E. Part exchanges welcome PARTRIDGE ELECTRONICS LTD BELCO M S S.M. H.P. and credit terms 6 Partridge House. Prospect Road, Broadstairs, CIO 1LD WESTERN ELECTRONICS S.A.E. all enquiries FD K. G3CED (Callers by appointment) G3VFA

542 RA DIO COM M U NICATIO N June 1978 YOU GET MORE FOR YOUR MONEY With the BUCCANEER 15 Watt 28/144M Hz Linear Transverter. Fitted with our Unique AUTO MATIC OVERDRIVE WARNING system setting up is simplicity itself. No more distorted signals due to excessive drive. Choice of 15 or 1 Watt Output levels at "The Flick of a switch". FEATURES: HI/L0 Switch for 15 or 1 Watt Output Unique AUTO MATIC OVERDRIVE WARNING system Relative RF Output power meter Accepts all modes—SSB, FM, CW. RIZ Front Panel controls Power ON/OFF Hl/LO switches Automatic Overdrive Warning LED plus Power on and Transmit indicator LED's Fused DC Power cord supplied Power Consumption at 13.8V DC Receive 1 00ma Transmit 1 Watt 700ma OTHER EQUIP MENTS IN OUR CO MPREHENSIVE 15 Watts 2.5 Amps RANGE INCLUDE —C ONVERTERS, TRANSVERTERS, Size 105 e 60 x 230mm AND LINEAR AMPLIFIERS. SEE PREVIOUS ADVERTS Weight 1 Kg. FOR LIST. Attractively finished grey hammer cabinet WRITE OR PHONE FOR FULLY DETAILED LITERATURE ON ONLY £79.00. for 15 WATTS. ALL OUR RANGE (inc VAT & UK carriage) ALL EQUIP MENT FULLY GUARANTEED FOR 12 M ONTHS. O M70 ELECTR O NICS LTD. SEVEFINSIDE SOUTH, BEWDLEY. WORCESTERSHIRE DY12 2DX Tel. BEWDLEY (0299) 400070.

QM 70 ELECTRON t. ,1,

SSTV & RTTY BARGAINS SERVICES NE W HBR TD224 RTTY VDU ONLY £160 A MC O M M S/H ROB OT 80A SSTV CA MERA MINT £190 i re 194A Northolt Road. South Harrow. Middx HA2 OEN Puces Include VA T 8. Carnage I red> Tel 01 -864 1 166/01 -422 9586

IMMEDIATE DELIVERY OF NEW ROBOT '400' SCAN CONVERTERS GU ARANTEE D USE D EQUIP MEN T (SA E f of full details please) With manuals and unmodified

AERO Et GENERAL SUPPLIES Triton II 10/80 Transceiver £355.00 Nanaimo House, 32 Ruttord Avenue, Brarncote, Nottingham NG9 3JH Yaesu FT101E Transceiver £395.00 Tel. (0602) 397588 KW200013 Transceiver 160/10 £195.00 Uniden 2020 Dig Transceiver £390.00 Yaesu FLDX 400 Transmitter £180.00 Yaesu FL101 Transmitter £330.00 Uniden 2020 DIG Transceiver £395.00 RZP ELECTRONICS FR101S Digital RX £285.00 Heath GR78 G.C. RX £62.00 Offer a comprehensive repair and maintenance service for Trio OR 666 RX £95.00 all makes of receivers, transmitters, transceivers, test Belco m 2M Linear 180 W £150.00 equip ment. ancillaries etc. Industrial Electronics and Drake R4B RX £180.00 professional com munications equpt. can also be repaired IC21 2MF M Transceiver/VFO £165.00 on site. Kyokuto DIG11 2M Transceiver £135.00 For Electronic repairs —see RZP. Trio IR 7000 G.2 M Transceiver £135.00 YC 601 DIG Display unit £80.00 Tel: Orpington 10A THE BR O A D WAY 20666 BEXLEY HE AT H ALL PRICES INCLU DE VAT KENT ALL ABOVE GUARANTEED 6 MONTHS

RA DIO CO M MU NICATIO N June 1978 543 G. W. M. RADIO LTD ALL PRICtS include VAT and Post/packing HIRE! BUY! or HP! PYE CAMBRIDGE U 10 8 UHF 70 (.:ms or FM108 Low Band Boot mounted RfT's. With Control box, cable and mounting tray No mike or speaker. Exceptionally clean as these have been used for data transmission only. £40 each. Two metre and 70cms SPEAKERS. Brand new mobile speakers by Lammerhold (type 232/3). Black plastic case, silver coloured grill, swivel bracket and 5 feet lead Rated at 2 watts 3 Receivers/Transceivers, etc, by ohms, £4.25. MICRO WAVE MODULES, ICO M, FDK. POCKETFONES PF1. A further supply of these hand held 430 Mc/sTxRx, again we are unable to test because crystals removed by supplier but these are just out of service With circuits and tuning Institictions. £20 parr (one Tx one Rs) Original. ASP ANTENNAE FOR 2 METRES AND 70 rechargable batteries, used but recharged and good, £5.50 pair. PF1CAR ADAPTORS Rs plugs in and battery is charged. Output is taken to a 3 watt C MS MOBILE, from £6.62 amplifier into 3 ohm speaker (no speaker supplied) £8. W ATCH OUR ADVERT NEXT MONTH, we shall be offering a line kit of boards etc. to make up a 144 Mc/s FM 25 watt transceiver All pans Factory fresh from a EXA MPLES: recently stopped production line. Details available soon with circuits and building IC-240 2 metre mobile Tx/Re fully synthesised, NO XTALS to instructions. send SAE if you want to eel in first. with 50p to cover printing costs. buy. Simplex. Duplex. Reverse Repeaters, Auto Toneburst. CALIBRATORS FREQUENCY CT432. 110/250 AC. 12' Y6 7h" 100kc/s. TO BUY: £189.00 1Mc/s and 10Mc/s outputs from integral crystals Provision for external crystals in TO HIRE: £14 per montn for 12-month period. the range 1001(c/s to 10Mc/s 4 front panel bases suit most types. RF sources may be fed in and calibrated by beatina aaainst desired crystal. Audio output to HIRE PURCHASE: Deposit £38. Over 12 months £14.60 per headphone socket. Clean and working order. £15. month. OSCILLOSCOPES CD523.S.2 SOLATRON. Clean and working order. £45. TOTAL PAID = 213.16 31 TRANSCEIVERS, no accessories. £8. R. F. FILTERS, clean up your supply Over 24 months £8.30 per month. leads, 25 amps at 250v AC or 600v DC. A Quality item. £1.25 or 5 for £4. A few TOTAL PAID =C237.00 PFI re.charaeable batteries. £5.50 a bait PLUG-INS for CD1212 OSCILLOSCOPES. Dual Trace Unit CX1252 or 40Mc/s ALL PRICES INCLU DE VAT. SEN D SAE FOR HIRE Wide Band Unit CX1251, clean and as bought from Ministry, £25 each. CON DITIONS C.R. TUBES for Hanley 13A 'scopes. £15. CALLERS ONLY. Various MF and VHF non-spec. Marine installations. Condition SEC ON D-H AN D BAR GAIN COR NER 'as is' to overhauled. from about £25. IC22A. 10 channels auto Toneburst A fine mobile Tx/Rx. 2 EXECUTIVE leather open•flat tool case, like brief case when closed. As new with metres. £120. keys, £12. EIC221 FREQUENCY METERS. Complete will charts, less power supply These are recently recalibusted. £20. MICR O WAVE M OD ULES TRA NSVERTER 144 metres to AKG Lightweight HEAD & MIKE SETS. model K58. Mike 2/300 ohms. 70cms - £125 headphones 75 ohms. Ideal for Mobile use and in excellent condition. £5.50. QUARTZ 162 metre Mobile Tx/Rx = £135 Carriage charges are for England and Wales only. Terms: Cash with order Early closing Wednesday All fro m G. W. M. RADIO LTD. 40-42 PORTLAN D ROAD, BOOTH HOLDINGS BATH W ORTHIN G, SUSSEX Telephone 34897 6 Golf Club Lane, Saltford, Bristol BS18 3AA Telephone Answering Service on Saltford (022.17) 2402 GADSG G3HEO After 7pm for G3NXU (B. Booth) Windsor (075-35) 51767 Bristol (0272) 712730 After 7pm for G8DPH (T. A. After 7pm for G3X013 (R. D. P. HOBBS LTD. Booth) Horsman) INCORPORATES HAM HIRE AND RENT-A-RIG ME MBER OF TAFA THE COMPONENT SPECIALISTS

SOLDERING IRONS. Antes C.C.N 15W. £3.93. C.X. 18W.. £3.67 X25. 25W.. £3.67 S 7.3 stand, £1.51 Dee Gee 25VV.. £2.93 ORYX Super 30. £3.78. ORYX 50 Temp. Control Iron. £8.53 ERSA Sprint L/W Solder Gun. £10.26. ORYX SR3A/S Solder Sucker. £5.94. Spare noz , 81p. P & P all. irons and acc. 25p each. ANTENNA FAULTY? TESTMETERS. Eagle C1050 20K 0 P.V. £12.90 Eagle C1095 with 4. pos. LOSIN G DX? Measure resonance and radiation resistance FAST meter. £17.00. I.CE. Microtest 80. 20K. 0P V.. £16.15 I C.E. Superiester... with an Antenna Noise Bridge, 1-150M Hz. 20200 ohms (2-1000 680R, 20K OP V. £27.27. P. & P. all meters. 75p each. ohms 1-30MHz). GET it RIG HT for only £8.20. CAPACITORS. 100pF 15V W.E.. 10p ea. 150pF 6.3V W.E.Mullard 510:20p RARE DX UN DER OH M? DIG IT OUT with a Tunable Audio 680pF 35V. W.E., 12p ea. Sprague 33000 35V. S.E. r r 1, 50p ea P. & P. Notch Filter, speaker amplifier, bypassed when off. only £7.90. 20p under £2.00 33000F 63V. 2-25A screw term, 45p. 33000 63V. 10 NE W! MSF 60kHz RECEIVER gives you digital SECONDS. Amp screw term. 60p P & P 25p ea 800pF 60V. screw term, 90p 100 MINUTES and output for MONTH. DATE and YEAR, internal 300V a.c work paper. 75p. 10uF 630V. d c. oil Idled crazier block. 90o. P. & P. ferrite rod, age, only £13.70. 50p ea. W.W Pots 25k 3W 1- •r spindle. 15p ea. 4P. 2VV. Wafer + DP SIG. GEN. 10Hz-.200kHz, sine/square only £9.80. Mains Rotary Switches. 15p. P & P 20p under 12.00. CLOBBERED? PUNC H THR OUGH with a Speech Compres- sor. always keep your audio at maximum AND get FOUR times NR56 VFI Monitor Receivers for 2 metres £54.00 TALK PO WER for only £8.60. YAESU FRG7 General Coverage Receiver .5-30MHz £162.00 NO LONG WAVE? 100 -600kHz to 80m Converter. £8.80. W HERE'S THE RARE DX? 1MHz, 100, 25kHz Calibrator gets FDK QUARTZ 16 2 metre FM Transceiver fitted 10 ch . £157.25 you SPOT ON. markers to VHF. connects between antenna and Also in stock . Microwave Modules Converters. Transverters and Counters receiver, bypassed when off. only £13.80. OM » Products Baniex Mobile Aerials and Mae Mounts Jaybeam Aerials. MISSING V.L.F. ? 10 -150kHz Receiver only £9.70. Prices include VAT LINEAR OK AY? Two Tone Oscillator only £7.40. Part exchange welcome Access or Barclay Card Each easy-assembly kit includes all parts. case, printed circuit, 11 KING STREET, LUTON BEDS. Tel: 20907 postage etc, money back assurance, so SEND off NO W.

NOW OPEN-D. P HOBBS (NORWICH) LTD CAMBRIDGE KITS 45 e irt ).0.. Idc S aincher gLeane,

13 St Benedict Street Norwich Tel 615786

544 RADIO COMMUNICATION June 1978 Optimum erformance with K W Decca-KW 103 Combined Swratt Power Meter is an I natrument for measuring e 50 ohm coaxial line feeding I an Aerial System or Dummy Load (1) Standing Wave Ratio. (2) RF Power with two reflues 0-100 a. 0-1000W when used with a 50 ohm Dummy Load. Decca -KW Dum my Load Is elr connection cooled and has been designed as a purely resistive SO ohm Decce-K W Salon filk.11. The load up to 30MHz. Power capability up to 1000W. Decca-KW 1000 Clecca-K W Belun Is broadband A idenev- Linear Amplifier —3 to 30MHz, rated up to 2KW for 19813 and C W p.e.p. 1:1 Ratio. 50 ohms 'un- 10-80 metres, 1200 balanced feed to lbelenced' out- watts input put. Waterproof moulded case. SSS. can be 'driven' Suitable for dipole and Beam by most 100 watt aerials. Tranocalvers and Transmitters. Em- Other K ploys a oelr of T180L Kw e..z W Tubes In grounded 48 grid. Pl.aectlon Input 4 Oh 'notch. NW the b _ 0 0,10, nd and output circuit.. 04440::*0 KW Bullt-In 2.41(v P.S.U. con.S WitCh.. Stockist& nw Antenna NOTE: The well-known KW LOW PASS FILTER pausing 3-30MHz Is Decca.K W 107 Antenna Tuning System Coe ociera tanci ,,- fo, H y.

available from stock. Incorpoentm E-Z mulch, SWRiRF Power Meter, A lle r R N itt O, s. " "I C I O , Dummy Load. Antenre swich. Kph power . 0 . y e r t O n Shur.. verelon KW 103 is mailable !locked ro 110 s e r vi n g R a di o A r n a t,, frru "I inimumme we, afj, manu ki. 1„re eq A mateur Radio Products DECCA CO M MUNICATIONS LTD Write or Wortd-phone for catalogue. '°"0 " fo, Cramptons Road. Otford. Sevenoaks. Kent 'Eats terms available on Tree 5EA. Tel: Sevenoaks (0732) 5001 equIpment over 12, 18 or 24 months.

TIVIP ELECTRONIC SUPPLIES THE AMATEUR RADIO SHOP Full range of most popular equepmenl In stock as listed in last months 10 CH APEL HILL, HU D DERSFIEL D magazine. Also: AMIDON IRON POWDER & FERRITE CORES Send SAE for Data W2AU BALLINS 1:1 & 4 1 Built-in lightning arrester £11.50 J FISH Tal: 20774 RAY HOYLE W2AU ALU MINIU M QUAD SPIDER • POA TECH (CEI) G810F TOROIDAL BALUN KITS 1 1 & 4:1 1kW Rating C3.50 G4MH MANAGER HF BAND UNIT £4.50 ROLLER COASTERS 24 Turns 4; x 4 x 3. Brand New £6.50 AGENTS FOR: YAESU, KW, FDIC, J-BEA M, SEM NYE-VIKING MORSE KEYS Brass Keying Arm Er Fittings £f3.75 160m Traps to make Top Band Dipole £9.00 SIG MA POWER METERS 2kW 3.5-150MHz £26.00 AL WAYS A GOO D SELECTION ALL ABOVE POST PAID OF SECONDHAN D EQUIP MENT Plus Coax, Plugs etc & lots of clean used equipment BUT WE NEE D MORE ... WHAT HAVE YOU? BRITANNIA STORES. LEES WOOD. MOLD. CLWYD CH7 4SD Open Daily 9 30-5 00 Tues close 1pm Sat 2 30pm RA117. RA17 Receivers in stock. SAE forSoec.from £240.00 Tel . Pontybodkin 846 (STD 035 287) New PSU 12V stabiliser 2-5 amp. incl. carriage £16.75 COAX SWITCH. incl. P&P .. £7.00 LOW PASS FILTER, incl. p&p £4.00 ORDINARY KEYS. incl. p&p £1.00 BUILT A PLX VDU? HIGH SPEED KEYS, incl p&p .. £2.65 MORSE PRACTICE OSC.. incl. p&p.. £3.50 Need an RTTY terminal unit to drive it? SWR9. incl p&p £9.00 We can supply, pc board with 741 active filters. 170 425 hi shift, SWR50A. incl. p&p .. £12.00 normal-reverse switch, direct interlace to UART input, meter circuit XTALS. over 3.000 in stock. at 75p each. built in. Pc board undrilled with into. £2.70 plus 20p p/p SEM PRODUCTS —FULL RANGE IN STOCK Pc board wired and tested, no switches. £28.50 plus 50p p/p Terminal units available for teleprinters also. SAE with all enquiries All prices include VAT SSTV pc boards still available Late night Thursday BARCLAYCARD Send SAE For Full Info until 8pm M.K. Products. 5 Lancashire Drive. Belmont. Durham. Enquiries fro m abroad VISA Or phone any evening. Durham 63111. Jarrow 898239. 4111kAccess welco me

RADIO CO M MUNICATION June 1978 545 RADIO UPDATE from GARE X (G3ZVI) We stock the popular NR56VF-1 2m He. with switched 144-146MHz VFO and 11 xtal controlled channels, ideal for fixed, portable or mobile use Built• in LS. 12V DC operation £54 inc. VAT (eats ..£2.50 each). NO W WITH IMPROVED VFO -EXCLUSIVE TO GAREX Lull Di_ Li INTERNATIONAL SR•9 Marine Band Ax (156-162 MHz) similar to NR56 £59.40 (mars A vastly expanded range of components for wireless is described in great £2.79) Sae for lull details. Credit facilities available detail in our 1978 cata aguo to whet your appetite, we describe some of Integrated circuits: 723 (T05). 75p; SN76660. 75p; CD4001AE, them here: 25p: NE555. 55p; 709 (005). 30p: 741 (OIL 8). 30p; 7410, 25p. ICs for radio old ones/new ones: Audio power (contd) Neons Panel mounting, type J H8, 8mm hole, 240V, red, amber or clear: CA3089E FM IF system 1.94 ULN2283B 0.8W/3-12v supply 1.00 35p each. any 5-, : 30p, 10+ 27p. CA3189E FM IF system 2.75 LM380N 2W AF 1.00 Miniature, wire end 8p each. 10+ 6.àp, 100 + 4p. HA1137W FM IF system 2.20 TBA810AS 8W 1.09 LED's Panel Mounting, type JH5. 6-5mm hole. red: 48p. green or amber: TBA120 FM IF system 1.00 TCA940E 10W /18v 1.80 72o Any 5 less 10% Any 10 - less 20% Resistor Kits. E12 series. 2211 to TM, bi values. b% carbon lilm, àW or TBA120S FM IF system 0.75 Traxsistors for new design% or to breathe .1W (please slate) Replenishments available uA720DC/CA3123E AM 1.40 wewhfe into ow; HA1197 linear age rf/if/det. 1.40 (3ipoiai signal irises loe iodic Starter pack. 5 ea value 12651 £2.95 Standard pack. 10 ea (5701 £5.44. Mixed pack, b ea àW • 5W (570) £5.4u Giant pack. 25 ea (1425) £13.25 TBA651 linear age rd/il/del 1.81 BF224 30v/360mW or or Ix drive .22 MC1350P linear IF gain block1.20 ,8F,247`,>1 PL259 UHF Plugs a- reducer 68p each. 5 -i- . 60p. MC1330 synch. demods+afc 1.35 S0239 UHF Socket panel mtg. 65p each, 45p. BF 241 40v/ 2W/400Mlix ilknot 022 NICAD RECHARGEABLES -physically equivalent to zinc-carbon uA753 limitin fer IF gain 1.80 OF T94/196 rerierrauxi0Sc 023 types AAA(U16) £1.64: AA(U7) £1.15; C(UII) £3.15: D(U2) £4.94:. LM1496N popular d.b.mixer 1.25 81-362 nf 4'4r:187800MHz loi UHF age RF (non) 095 PP3 £5.20. ANY IS+ less 10%. ANY 10+ less 20% TDA10133 one IC COrnrnS. ro 1.95 8F4 79 Et 1800MHx. nf 4',d8/800MHr Slide switches. min DPOT 18p ea: 5 14p 2P3W 22p ea.. 5 • 18p. TDA1062 one IC front end 1.95 ultra linear ri stage Comp, 0.80 Toggle switches, min lull range SP thr0' to 4P C/0 sae list. HA1156 (MC1310P1 mpx plus BF6796 nf3SidE1/800MH, with 1545 GAR D( FM detector and squelch conversion ready assembled with gain es rf stage twits) 0.70 general PLL applications 1.25 full fitting instructions. Tailor made, easy-fit design for AM Cambndge. BFW92 It 1600MH,, nf4dB/500MFIr replaces squelch board with minimum of other modifications. £5.40 KB4400 refined 1310Plincledl 2.20 excellent iniermod. Inpril 0.72 Transistor Vanguard (AM25T) version with modified squelch circuit. CA3090A0 RCA pli decoder 3.75 T and MOSFET OF900 of 2tIB/200MHr. replaces £5.94. HA1196 adjustable sep. dec. 40600/40673 ere 0.80 oder with o.o4% THD 4.35 CRYSTALS FOR 10 METRES: 0-1C25U) 28 500MHz Tx - plus EiF680 as 8F900 7092 0.75t 28 045MHz for R. (455kHz IF) suit most -C B £4.50 pair SD6000 dual DMOS RF/mix 2.35 40673 famous RF!IF amp 0.551 AUTHORISED DISTRIBUTOR FOR REVCO (AERIALS) AND TDA1220 AM/FM 11F/IF 1.75 DIGITAL devices for radio uses SP/DM8629 divide by 100 10150nd-1z 4 201 J. H. ASSOCIATES (SWITCHES & LAMPS) AUDIO ICs new blood here: It 030 divide by 10/11 10 650MHz 14 00? ITE MS AS APRIL AD STILL AVAILABLE TDA2002 8W/2L1 mobile power rioter's inns mow on tee now Water». • from 14.4v supply 1.75 wino or (an el ar ou, new pronnie N5p1 PRICES ARE INCLUSIVE OF UK POST AND PACKING AND VAT Please note: All prices exclude VAT which is 12.5% other than where GAREX ELECTRONICS 7 NORVIC ROAD. M ARS WORTH, marked t In). Postage 25p per order. Phone 10277) 216029 (after pint TRING HEATS HP23 4LS M AIL ORDER ONLY 2 Gresham Road, Brentwood, Essex. CM14 4HN . Parking outside the door, Phone 0296 668684 6.30p m 9pm & weekends only only 200m from Brentwood 1BRI station Passive components now available.

BREDHURS1 ELECTRONICS R.T. Et I. offer the finest selection of FOR VHF ON THE SOUTH COAST first-class new and fully overhauled FDK MULTI Ull 70cm fitted 9 channels £249.00 second-hand communications and MULTI 2700 2m all mode £489.00 TM568 Scanning 2w RX fitted 10 channels £85.00 electronics equipment in the U.K. TM56B Marine Monitor fitted 10 channels £98.00 Constantly changing stocks of a vast range of Quartz 16 2rn FM fitted 10 channels £149.00 • MULTI 800D 2m FM Digital £239.00 equip ment. • Cash or Hire Purchase ter ms easily arranged. ELECTRONIC DEVELOP MENTS e Part exchanges welco med. 2rn linear 100W output £151.00 • W e are 'spot cash' buyers for almost all electronic YAESU equip ment. FRG7 Gen coverage AX £162.00 Send SA E for our latest fist of over 50 receivers and many other Interestinç 1509.00 Fri 01E HF Transceiver items ANTENNA SPECIALISTS ASP 677 2m a wave £14.95 R.T. Et I. ELECTR ONICS LTD. ASPE 667 70cm 5dB collinear £19.04 Ashville Old Hell, Ashville Road, London E.11 Tel: 01-539 4986 ASP2009 2m a wave £7.95 ASP Magnetic Mount £8.50 No-hole Boot Lip Mount £3.50 NAGAI SAMSON ETM - 3C KEYERS 144XL 2rn Linear 250W output £399.00 DENTRON Professional-grade C-MOS keyers built for dependable Marine Ft COnsinercial MLA 2500 2kW HF Linear £699.00 use world• wide - Backed by Spacernark service MT 3000A 3kW ATU £275.00 Only leA battery idling current I ETM-3C. f63.88 160 Al IkW ATU £99.50 ETM 4C ME M ORY KEYER -Has ETM 3C features plus 4 memories each JR Monitor 300W MU £59.00 taking approx 22 Morse characters (switchable 4 256 or 2.r 512 bits) J-BEA M Erase/rewrite as often as needed By lust pressing a button 4 sends COs etc - 9502 VHF Rotator £45.00 MINI-PRODUCTS once only. cm repeatedly, and at any chosen speed Mal Minihrsam 94.75 JUNK ER PRECISION HAND KEY. £36.54 Constantly changing stocks of S/H gear-ring for details BAUER SINGLE-PADDLE KEY UNIT. £11 66 HP PART EXCHANGE ACCESS BARCLAYCARD 88mH TOROIDS Ira, lily cm, sstv. filters. 90p each CALLERS BY APPOINT MENT ALL PRICES INC. VAT SSB 90' AUDIO PHASE SHIFT NET WORKS, octal based THE STREET, THAKEHA M All prices postpaid and include 12.P. VAT Please send stamp with all PULBOROUGH, SUSSEX. enquiries Tel West Chiltington (07983) 3056 SPACE MARK LTD THORNFIELD HOUSt. utLA MER HOAD. ALTRINCHA« M. Distributor for Waters and Stanton G30QT CHESHIRE (Tel. 061-928 8458)

546 RADIO COMMUNICATION June 1978 ADVANCED PRODUCTS FOR THE DISCERNING AMATEUR FREQUENCY-AGILE AUDIO FILTER RF SPEECH CLIPPER MODEL FL1 M ODEL RFC A versatile bandpass or band- Processes speech as a SSB signal al reject filter with hilly variable 60kHz to increase its ratio of average bandwidth end centre fre- to peak levels without adding her- quency plus unique search monic distortion. Improves talk /lock/track capability for auto- power of SSB. FM. and AM trans- matic removal of heterodyne mitters without increasing the peak •_i whistles. Improves reception of transmitted power Connects be- eie• •.. CW. ATTY. and SSB. Connects tween microphone and transmitter. between receiver and (See articles by Dr D. A. Tong, loudspeaker Wireless World. Feb. 1975, 79-82 and Oct. 1976. 77-81). UP-CONVERTER MODEL UC/1

Adds full receiving coverage M ODEL AD170 (Not illustrated) from 90kHz to 30MHz to exist. mg receivers or transceivers A compact active receiving antenna covering 100 kHz tuning 28-29MHz or to 70 MHz without tuning or matching units. Please 144-145MHz The full range is see previous ads. For full description, or send for data covered in thirty 1MHz wide sheet synthesiser controlled seg- ments. Also works as a two- MODELS MPU AND MPU/I metre converter. Connects be- Mains power units for FLI. UC/I or AD170. MPU has tween receiver and antenna. integral 13A mains plug. MPU/I has 18" mains lead

PRICES: (NOT INCLUDING VAT) AD1 70 £29.50. MPU and MPU/1 £5.50, AD1 70 -1- MPU or MPU/1 special package price £33.00. ELI £53.00. UC/I £105.00. RFC £40.00, RFC/M £21.50 (PCB version of RFC). All prices are subject to VAT at 12e,. Prices include delivery within UK. More data on any product plus complete price list showing accessory leads. etc. available on request.

D AT O N G ELE CT R O NIC S LIMITE D DSpence Mills. Mill Lane, Bra mley, Leeds LS13 3HL Tel: Pudsey (0532) 552461.

T.D.S. PIP TONE For SSB use on 144MHz or above, this PCB produces a short tone (G M2F H H) on release of the P.T.T. Simply connects into microphone lead. L. HARDIE Suitable for use with high or tow impedance microphones. The W orker Bee's sting is approxi mately 4m m long Adjustable 0/P level and frequency. (the other 10 inches is your imagination). But there's no Fully isolated relay P.T.T. 0/P (for rigs with diode c/o). Size: 2" x 2" x ". Power 9-15Vde. Price £5.95. sting in the tail of the offers we make, in fact they are the Bee's Knees, 2 METRE PRE-A MP As previously advertised. Uses SD306 to achieve superb £168.00 cross-mod. performance and low noise. YAESU YC-500-J Freq. counter FRG-7 Gen. coy. AX £162.00 Price £6.50 FT-227R 2m FM transceiver £189.00 C.W.O. Mail order only - 300 p&p on all orders. OTR -24 World clock (battery) €25.66 T.D. SERVICES, P.O. Box 27, Ruislip, Middlesex HA4 7Y0. DRAKE SSR•1 Gen. coy. AX £150.00 GRUNDIG Sate/il 2100 £220.00 SSB- 2000 adapter £23.35 FM CRYSTALS BY RETURN POST SMC Monitor Scope 176.00 70cm Channels $U8. $U20. RBO, R82. AB& ABS. RB10, RB14 SCOPEX Oscilloscope type 4S-6 £170.00 12MHz Tx and 84MHz Rx in HC18/ U (Pocketphone) JAYBEA M Most models ex stock 24M Hz Tx and 34MHz Re in HC25/U (Starphone) ROTORS stone 2010 £49.00 2 metre Simplex SO. $8. S16. $18, S20-25. S32 Kenrotor KR•400 (Similar to CD-44) £95.00 Repeater RI -FIS USED EQUIP MENT (at time of going to press) Tx ranges 4. 8MHz In HC6/U; 6. 12. 18MHz in HC25/1.1 Drake SSR-1 as new £130.00 R x ranges 10. 44MHz in HC6/U; 14. 44, 52MHz in HC25/U Heathkit HR -1680 Hamband AX £160.00 Inclusive price £2.90 each 10% discount on IA or more 10 to 80m as new Heathkit DX•100/SSB SB-10 adapter £75.00 Made-to-order crystals 2-105MHz 3Oppm £3.60 each. del. within 6 Yaesu FT-21 all mode CW/AM/FM/SSB £320.00 This is a demonstration model and definitely as new. A real snip HARTLEY CRYSTALS Phe:rarm Teleprinter; Creed 78 with Power unit and Terminal Unit type AP-100386 (in Green Lane, Milford, Godal ming, Surrey GU8 5B G working order with keyboard and lots of soares1 £60.00 Heathkit SB-220 Linear as new, save SPECIAL OFFERS t64 on this one and it's ready to go £400.00 UR76 COAX 50ohm stranded conductor 6mm die c. 14p per Metre Post 21p per Metre S.A.E. all enquiries please UR39 COAX 75ohm. low loss. similar to UR67. single conductor @ 20p per Shop hours 0930 to 1300 and 1415 to 1730. M poor 4e Per M UR95 COAX 50ohms. miniature Nylon. 2.3mm cha e 5 per M post 1p per M Early closing W ed. 3000hm RIBBON Twin Ribbon @ 8p per Metre post 1;ta per M. Compare these prices and see how much you save .. A SAE will bring lull lists of 542 George Street, Aberdeen AB2 3XL Cables 8i Xis's etc W.H. WESTLAKE. G8M W W. CLA WTON, HOLS WORTHY. DEVON Tel: 0224 20113

RA DIO CO M M U NICATIO N June 1978 547 ABSORBTION WAVEMETER TC101 COMPONENTS AND MODULES ALL OUR DEVICES ARE TO MANUFACTURERS FULL This unit, with our CC10 crystal calibrator, fulfils frequency measurement requirements for the Amateur Sound Licence and is SPECIFICATION: used by the Home Office. 800kHz to 500 M Hz in six switched BC107 12p BFY 90 £1.05 ZTX502 £0.18 N4001 5p ranges, sensitivity 100mV for 20% FSD. Calibration accuracy BC108 12p BLY 33 £1.00 2N3819 £0.35 N4002 6p 2%. Complete with probe and handbook. BC109 12p BSX 19 2N3866 £0.87 N4003 7 P £36.95+ VAT, P&P incl. BCY70 17p 2N2368 £0.16 2N4427 £0.92 N4004 8p BCY72 15p BSX20 £0.14 2N3553 £1.44 N4005 9p R's, C's, TRIMMERS Et HARDWARE BD106 42p SD306 £1.62 40312 £0.55 N4006 10p RESISTORS 1 and waH 5% E1210 D-1 M D, £1.92: 10-99 £1.20 BFR99 65p N4007 11p 40673 £0.62 10% off each value 1W total 610 resisters, £5.40 +VAT (H) BFY51 18p N4148 3p PRESETS 1, 2-5, 5, 10, 25. 50. 100. 250. 500k +.1 MD, 8p + VAT (H) Components for G3MFJ/G3KEP frequency counter: 25+ mix we pay VAT PANEL POTS Lag/Lin. 34p each +VAT (H) 7400 13p 7475 47p MC10116P 65p IN4005 9p M ULLAR D CAP ACIT ORS min cera mic plate 63V/100V. 2P2, 7413 30p 7490 47p MC10131p £1.67 Other 3P3, 4P7, 6P8, 10, 12. 22, 33. 39. 47 pf. 3.5p each. 68, 82, 100 pf, 7447 68p 74121 34p NE529K £1.62 74IC's 4-5p each. 680. 1000. 10.000 pf. 4p each. 5 of each value, total 90 7473 31p 74196 90p MR5V £1.49 Available caps. £3.05 + VAT (H) ELECTR OLYTICS 1p, 2.2p, 4.7p, 63V; 6.8p, 40V: 10p, 25V; 15p, 5 pole11 way rotary switch É3.10. 50k panel mtg pot 34p (H). Disc ceramic Caps 1pf- I Onf. 1-24 3;p 25-99 3p (H). 16V; 22p. 25V; 47p, 10V+ 40V: 68p, 16V; 1--24, 7p; 25+ mix, 13p. 220p, 16V. 13p. 470p. 40V, 46p. 5 of each value 1-220p incl. total 12 & 24 HOUR DIGITAL CLOCK MODULES 65 caps £4.10 +VAT With alarm facility. Complete unit. only requires transformer. setting switches MINI POLY TRIM MERS 1--6p. 13p; 2-10p, 13p; 2-22p, 14p: and case. Types MA1001F and MA1002 (H). Manufactured by National 6-65p, 19p. Semiconductors Prices: 12 hour. £10.20+ VAT. 24 hour, £14.80+ VAT. HAR D WARE: 8% VAT, 35p p&p. Prices per 100 NUTS 2BA, 56p; 4BA, 47p; 6BA, 38p; 8BA, 56p. APPLICATIONS MANUAL No.1. BOLTS Cheesehead cadmium plated: 2BA x 1". 60p: 4BA x 1", Theory and applications of Resonant Circuits in oscillators, amplifiers, filters, detectors. mixers, multipliers covering 85kH-205MHz, together with circuits 60p; 4BA x ¡". 91p; 6BA x ,Pa", 52p; 6BA x 1". 52p. Round head and results. Block diagrams show combinations of circuits for receivers, low chrome: 6BA x 1"; 6BA x r, both 90p. power exciters etc. Available now -price 60p post free and Zero Rated VAT SOLDER TAGS Single or double-ended silver plated: 2BA. 4BA 6BA, 8BA, all 29p per 100. S. R. Marsh D. A. Jackson S. E. Hand VAT No 219 1165 80 TAPPE D RO UN D SPACERS6BA u1" or1". 21peach. 4BA x r or Add 12-5% to all items marked (H). 8% to all others P&P 25p. i", 31p each. BURNS S . C. S. 4s 3ijaR CR HE yl P cS RT 3E A2DR BV ALLEY RD. 0C1 6U6L8SD 7706N 6

Sensational 1 OFF CRYSTAL PRICES value in Fundamentals -C-elitC electronics Group Price 10 West Park London SE9 480 quartz 1 0.030 to 0 099MHz 100ppm £14.26 crystals 2. 0.100 to 0-369MHz 100ppm £9.75 Telephone 01-852 9397 3. 0.370 to 0 730MHz 100ppm £10.00 We are now re-introducing our crystals for popular frequencies at the 4. 0 731 to 1.499MHz 100ppm £9.75 1974 prices. We can't promise how long this offer will last so buy now 5. 1 500 to 1 999MHz 3Oppm £3.45 to take advantage of quality quartz crystals at realistic prices. We also 6. 2-000 to 3 999MHz 3Oppm £3.00 continue to offer 1-off crystals over the complete range from 30kHz to 7. 4-000 to 20 999MHz 3Oppm £2.85 216 MHz, so for a comprehensive crystal service for amateurs and 8. 21-000 to 24 000MHz 3Oppm £3.25 professionals alike C&C is the answer. 3rd Overtones 9 21 000 to 63 000MHz 3Oppm £2.115 TWO-METRE FM CRYSTALS Specification normally i3Oppm -30 to 5th Overtones -60'C. ±1Oppm at 25'C in HC6,HC18 and HC25/U holders. When ordering 10. 60000 to 104 999MHz 3Oppm £2.95 please give crystal's load capacity and holder or specify equipment in which 11 105 000 to 119 999MHz 3Oppm £8.25 crystals are to be used. 12. 120 000 to 130 000MHz lOpprn £12.00 5th, 7th and 9th Overtones TX 4 to 4.06MHz. 6 to 6.084MHz. 8 to 8.12MHz. 12 to 1217 MHz. 18 to 13 130001 to 216 000MHz 10ppm £20.00 18.25MHz. RX 10.2510 10.4MHz, 11.1 to 11.28MHz, 1481 to 15.04MHz.44-43 to 45-10MHz, 51 56 to 52.24MHz. Unless otherwise requested fundamentals will be supplied with 30pf load Normally in stock R3 to R7, SO S20 to S23 and 532.12 & 44MHz 'for TR2200. 4 Ad capacity and overtones for series resonance operations. 8MHz HC6 TX, 44MHz HC6 & HC25 RX. Many others, send sae for'list. If not in stock delivery normally four to five weeks PRICE £1.95 HOLDERS 30kHz to 200kHz HC13/U. 170kHz to 196 000MHz HC6/U, 4-000 to 216.000MHz HC1 8 or HC25/U. Prices on application for other holders. CRYSTALS FOR JAPANESE TRANSCEIVERS 2 METRES AND 70cm Crystals supplied to the above specifications for your 2 metre and 70cms DELIVERY: Groups 1 to 4, 12 and 13 - six to eight weeks transceivers. d not covered by the above category. Also Pye UlOB and W15U. Groups 5 to 11 -.four to five weeks Delivery lour to five weeks Please state holder required when ordering ANY FREQUENCY INCLUDING MARINE CHANNELS PRICE £2.25 DISCOUNTS (Only applicable to Groups 1 to 13) PYE POCK ETFON E RECEIVE CRYSTALS 5% mixed frequency discount for five or more crystals within any price group. For HC18/U between 84.46 and 84 86MHz ±lOppm at 25'C Delivery four to five orders of same frequency and specification discounts start at five off in groups 1 to weeks. PRICE £2.50 (TX crystals £1.95) 4, 12 and 13. In all other groups discounts start at 10 off. Special rates for bulk purchase schemes including free supply of crystals for UK repeaters CONVERTER CRYSTALS IN HC116/U 96.0000. 101 0000 and 116.0000MHz in stock PRICE £2.95 27M Hz CRYSTALS IN HC18 or HC25/U TONE BURST AND IF CRYSTALS IN HC18/1.1 For EXPORT or radio control applications, small quantities PRICE £1.50/crys- 7.168MHz for 1750kHz and 10-245MHz for 10.7MHz IFs PRICE £2.25 tal. For larger quantities, price on application. EQUIP MENT SUPPLIERS MINIMU M ORDER CHARGE £1.50 Please note we can supply crystals suitable for VHF transceivers Save delivery All prices include postage to UK and lush addresses. Crystals supplied to any worries and pay in STERLING. 101 off same frequency. PRICE £1.10/crystal specification for industrial, mobile radio or marine use etc. State LOW FREQUENCY STANDARDS (8% VAT) 100kHz in HC13/U, PRICE equipment/specification when enquiring. Please send postage stamp with all £2.95. 1000kHz in HC6/U. PRICE £2.80. 10-7MHz HC18/U Price £2.26. enquiries. CRYSTAL SOCKETS HC6/U and HC25/U PRICE 16p PRICES ARE Ex VAT PLEASE ADD 12;% UNLESS OTHER WISE STATED

548 RADIO CO M MUNICATION June 1978 CLOSED G8CCIS WEDNESDAY MODULAR ELECTRONICS AFTERNOON 95 HIGH STREET, SELSEY, Nr. CHICHESTER, SUSSEX. DISTRIBUTOR FOR THE PRODUCTS OF SOLID STATE SCIENTIFIC INC Telephone: Selsey (024-361) 2916

Type Specification Frequency Price Signetics - 13" MOS SD306 Enhancement Mode PLUGS AND SOCKETS. (Cone) an ,8% VAT + VAT 8% NF MOSFET 1.5dB, 144MHz, CCT and Data £2.00 BNC 50ohm Plug 589. BNC 1 hole Socket 55p. Surplus. Equiv 2N5947 CATV amp FT 1200MHz "N" Plug for y coax 50p. 4.hole BNC 50p 2N4427 1W 10dB 12V 175MHz £0.84 High gain stud mount 5W diss In-House Coded 70p INTEGRATED CIRCUITS. VAT at 8% 2N3866 1W 10dB 28V 175MHz £0.78 Texas 3rd Generation MOSFET 3N204 Elect same Motorola MCI 2013 - 10 prescaler with TTL output 2N5913 2W 7dB 12V 470MHz £1.40 40673 with vastly better Noise Fig Used in PA1 5V supply with data/input amp CCT £10.50. 2N3553 25W 9dB 12V 175MHz £0.95 £1.20 4 8% Mc1495L £1.75. MUS 4001 113p. 2N6080 4W 12dB 12V 175MHz £4.00 Small Signal Transistois 8% VAT CAPACITORS. 12.5% VAT. 1000p1 disc 200pf SD1143 10W 10dB 12V 220MHz £5.70 40673 75p, 2n2369 15p. 8C107 12p. At 8p disc. 33p1 disc. all 2.5p. 2N60131 15W 6.3d8 12V 175MHz £5.50 + 125% BC149. CIL108= Plas BC108 Feedthr Solder 1000p1, 50p1, all 8p. 2N6082 25W 6 2d8 12V 175MHz £7.50 Dual VHF/UHF FET E420 (Dual E300) in•house No UHF Micadisc 33 and 22p1 all 8.P. 2N6083 30W 5 7d8 12V 175MHz £8.40 Ideal tor Mincis, etc. With Data £1.00 + 8% VAT Equipment Details and Prices as May Advert. 2N6084 40W 4.5d 8 12V 175MHz £11.10 Antenna Relays Mag Den 951.170.12V 50ohm 2N5642 1W- 10W @ 138V. 2W 13W @ 13.8V; RF2127 70W 6,6d13 12V 175MHz £23.50 good to 1296MHz RG43 cable entry £6.20 +8% 1W =20W @ 28V With circuits and data. SD1019-5 100W 6.0d8 28V 175MHz £18.70 £3.25+ 8%. 2N5590 10W 5.2d8 13.6V 175MHz £4.70 H EATSIN KS. Single sided. REDPOINT. VAT + 8% Fingering for 2C39 etc. 40p 11+ 8%. 2N5591 25W 4.4dB 136V 175MHz £6.80 4Y1 45 deg C/W 4' x 2-36" £0.70. BER15 (13FF134 in TO72) 2.5d13 NE 500MHz. 2N5944 2W 9d8 12V 470MHz £5.40 £1.75+ 8%. 6M1 26 deg C/W 6' x 369 £1.30. 2N5945 4W 8d8 12V 470MHz £7.60 TAA263 aud cct 77dB gain TO72 can, 85p+8% Post 259 on heatsink ONLY due weight. 2N5946 10W 6d13 12V 470MHz £9.50 MBD102 HC diode. 90p •+ 8%. S131136 10W 5.5dB 12V 470MHz £6.40 50 ohm 4-hole BNC sock. 50p+8%. S01088 25W 6.8cIB 12V 470MHz £16.45 New 0240G 107 Xt1 lilt. 910 ohm/25p1 COMPONENTS. VAT 12.5% unless marked ITT S131089 40W 4.3dB 12V 470MHz £19.50 375kHz £7.00 + 8%. DAU PTFE 7mm Trim C 1 5-Spi or 2-18p1 18p. 2N5179 Gen purpose amp. FT =900MHz £0.72 Mullard 7mm Trim C 1.6pf 16p. ITT 014DG 107 Xt1 lilt 825 ohm/25p1 175kHz BFX89 UHF amp FT 1100M Hz TO72 £0.90 Surplus lOmm Trim C 25-25p1 9p. £7.00+8%. EIFY90 UHF amp FT 1000MHz 7072 £1.00 Min 10-7 interstage XII lilt. 25kHz (2+8%. TETFER PTFE (UHF) 2-10pf only 25p. BLW16 1W/1.4W 175MHz 13.6v TO39 709+8%. CERAMIC 7mm Trim C 35-1301 9I) 2N918 30p, 6E528 75p. BB103 25p. TIL209 LED TRW Super Low Noise ''T" Pack (same CLYDON MICA 10 -60pf good RF power 15p. BFR90/911 AS Mica 4-40p1 good RF power 20p. 8p. all 4 8%. TP393 2 OdB NF at 500MHz £2.00 Min RF Chokes. 20 and 10000 at 12p ea+ 12,5%. Postage: 35p up to £20 value. Above £20 add TP491 1 6d6 NF ai 500MHz £3.10 FERRITES. FX1115 1 hole 4p. £1.00 for post/insurance. BER90 3 2dB NE al 1250MHz £3.50 FX1898 6 hole 10p. FX2049 2 hole RF trans 10p all Minimum order £1.50 Min VAT free export £15. BER91 2 5dB NF al 1250MHz £4.00 8% VAT B/CARD or ACCESS over £10

NO DATA CHARGES. WE NO W HAVE PLAIN PAPER COPYING. IMPROVED DATA.

A small selection from the free Heathkit catalogue.

HW-101 Send for your copy now. Receiver 1E1 Sensitivity • 0 350 loi 10dB S • N N This is just a small selection tor SSB oPetaltati from the Heathkit Catalogue- Output Impedance 8.C1speaker and high o packed with more than 200 impedance headphone top quality kits for radio and Spurious Response Image and IF 111 reiection • 50dB HW-101 de-luxe 5 band transceiver electronics enthusiasts. Transmitter £361.13 inc. postage. DC Power Input' SSB 180W PEP (norma) HP-238 fixed station AC power supply for 1M-4190 NEW bidirectional FiF vorce, continuous duly cycle) CW 170W tIW 101 £53.82 Inc postage. Wattmeter £69.51 inc. postage 150% duty cycle) HP-138 mobile power supply for HW•101 HD-1426 Field strength meter fle;ltfkltithk RF Power Output 100W. 80. I 5m £82 36 Inc postage £11 04 inc. postage. , rages Cii rah )gue. 80W, 10m mu am ow am ma packed tedh colour General Over foP Qualify kds Frequency Coverage 80- 10M amateur I Send for your free Heathkit Catalogue! bands I To: Heath (Gloucester) Limited, Department RC68, Bristol Road, Gloucester GL2 6EE. Frequency Stability 100Hz hr drift after 45 min warm up from normal ambient ▪ Please send a copy of the Heathkit Catalogue. I enclose Ilp in stamps to cover postage only. conditions I N.B. If you are already on the Heathkit mailing list you will automatically Audio Frequency Response 350 to 245011z receive a copy of the latest catalogue without having to use this coupon. The world's IM-4190 biggest producers Power Ranges Forward. 30. 75 and 300W of electronic kits. lull scale Reflected, 3, 75 and 30W full ▪ Name scale I Address Frequency Range 100Mz to IGHz. I mpedance 50n Accuracy • 5-i, of forward ranges - 7 5", ol reflected ranges U M Size 4 5in (H) x 4 25in (W)x 4 6in (D) L Power Requirement 9V battery (PP3i There are Heathkit Electronics Centres at 233 Tottenham Court Road. London (01-636 7349) and at Bristol Road. Gloucester (Gloucester 29451).

RADIO COM MUNICATION June 1978 549 NUNSFIELD HOUSE CO M MUNITY ASSOCIATION G8CZ W A MATEUR RADIO GROUP: G3EE0, G3Z81, G8KGC Digital present the Ninth Frequency Meter ELVASTO N CASTLE Complete 50M Hz kit £54.00 inc VAT, post free (UK) M OBILE RADIO RALLY ZN1040E Count/Display IC 8.10 Hardware and Wire Pack 1.45 Integrated Circuit Pack 9.26 Case. Two-tone pvc-faced Sunday 11th June 1978 Displays and Filter Pack 7.78 steel, punched and lettered Semiconductor and Diode Pack 2.47 (+95p P & P) 6.76 Resistor and Capacitor Pack 3.10 Min BNC Sockets (500) 0.86 Elvaston Castle countryside park -sho wground Logic and Display PCBs 4.84 Min BNC Plugs (500) 0.70 5MHz Crystal 3.45 500MHz Prescaler Kit 1.78 5 miles S.E. of Derby on the B5010 (sign-posted) Transformer 8-0°V0.5A SP863113 500MHz IC 8.98 ( -75p P & P) 2.48 NE592 Wideband Video Amp 1.43 Switches, Knob. BNC's etc 4.15 OEM Reprint (post free) 0.50

OVER 40 TRADE STANDS NE W! Hi-2 Buffer Kit enables DFM to count below 100Hz £6.50 (inc P & P) M any attractions for all the family. I.B.A. Oracle demonstration, side shows, childrens' rides, G8CZ W communications display by TAVR, & much more Digital GIANT BRING & BUY STAND Voltmeter

R.S.G.B. BOOKSTALL Complete kit £44.30 inc VAT, post free (UK) REFRESH MENTS E ZNA116E 34 Digit IC 6.48 Hardware and Wire Pack 1.20 TALK-IN Integrated Circuit Pack 5.24 Case. Two-tone pvc-faced G3EEO/P -160m; G3IBI/P-2m (S22). G8KGC/P-70cm (918,1SU20) Displays and Filter Pack 7.78 steel, punched and lettered Semiconductor andDiode Pack 2.60 ( +95p P & P) 5.75 Further infor mation: I. Cage. G4CTZ Resistor Pack inc cermets 4.64 IC Sockets Pack 1.08 25 Petersha m Drive, Alvaston, Derby, DE2 OJU Capacitor Pack 1.68 Transformer ( +75p P & P) 2.48 Logic and Display PCBs 2.05 Tel: (0332) 71875 5V Reg, 2 Rect. 2,000pF Voltage Attenuatar Pack 0.68 Cap. Mains SW. Fuse and Range Switch 6P 4-way 2.38 Holder 3.75 DVM Reprint (post free) 0.36 All prices inc VAT at the standard rate. Please add 20p P & P for packs. SAE for full Designer lists. TO WERS Oversees-Deduct 8% off these prices approved "Mosley"-the tested ROTATORS COAX and proved Antennae ROPES ELECTRONICS (OLDHA M) LTD 83 Lees Road, Oldha m OL4 1JVV Send for HANDBOOK containing full details of Antennas and Tel 061-624 8812 other technical information. 33 pages 60p. Refundable upon purchase of Antennas. CASH & CARRY WAREHOUSE PRICES SO ME ANTENNAS Large stocks of Sony Hitachi National Mitsubishi Toshiba Dynatron and all Mustang 3 Elements, 10, 15 and 20 metres . £118.00 leading makes of Radio TV Ni. Fr Fridges Freezers & Washers TA-33 Jr. High power Model incl Balun SPECIAL OFFER National DR48 £269-95 HP Available. 3 Elements, 10 15 and 20 metres .. £108.00 LW. MW. VHF plus 75W Digital Readout S-meter NL BFO Batt or Mains TA33 Jr. 3 Elements, 10 15 and 20 metres .. £95.00 Also on olio( Sony CAF 5900 £74.50 CRF 5090 £159.50 CRF 320 £745. Established over 50 years based on firsuclass after-sales service TA32 Jr. 2 Elements, 10. 15 and 20 metres .. £64.00 Please enclose large S A.E with enquiries or call at our showrooms TA31 Jr. Rotary dipole, 10. 15 and 20 metres £40.00 G3ST PARK ELECTRIC CO. LTD G8HGE ELAN 3 Elements, 10 and 15 metres .. £76.00 211 STREATHAM ROAD, MITCHAM SURREY 01-648 6201 TD-2 Trap Dipole. 40 and 80 metres . £33.00 TCD-2 Trap Dipole. 40 and 80 metres compressed . . £40.00 CHASE ELECTRICS LIMITED V-3 Jr. Trap Vertical, 10. 15 and 20 metres . £29.00 Vacancies exist for engineers and technicians to work on the Atlas Trap Vertical, 10, 15,20 and 40 metres £50.00 design, test and manufacture of radio test instrumentation. We are S WL ANTENNAS a small expanding company and can offer interesting and varied S WL-7 Dipole 11. 13, 16, 19, 25. 31 and 49 work. metres .. . £27.00 Salaries range from £3,500 to £7.000 depending on position and RD-5 Dipole 10, 15, 20.40 and 80 metres £27.00 experience. Orbit Vertical 11, 13, 16. 19. 25.31 and 49 Telephone: 01-977 0251/2 metres .. • £45.00 Prices correct at time of going to press

MOSLEY JAMES Er MARTIN ELECTRONICS LTD 196 Norwich Road. ELECTRONICS Staines Road. Feltham, Middx. LIMITED New Costessey. PROTOTYPE AND PRODUCTION METAL W ORK Specialists to the Electronics Industry. Panels, chassis and sheet Administrative Address Norwich NR5 OEX metal details. Milling, turning. drilling. Machining in all metals only ENGLAND and plastics. G3VVB.

(All antennas available ex works carriage and VAT extra) Tel. 01-570 3127 OS Ref TG 113748 Plant list on application.

550 RA DIO CO M M UNICATIO N June 1978 A M ATEUR RADIO e %‘o 9 .iet EXCH ANGE S re‘ Proprietors: Brenda Aptaker, Bernard Godfrey (G4A0G) el e Buying or selling, we invite you to come and look over the extensive and ever-changing stock of secondhand equip ment in our shop on the corner- majo r items and accessories. And, if it's new gear you are after, we are stockists of (among others) Yaesu. Ico m. FDK. Standard, Micro wave Modules, Q M70, KW, Antenna Specialists and Bantex. So, come and see us first. Even if you don't buy. you'll be glad you did .. . because there's always a warm welco me, and a cup of Brenda's coffee!

LEA DIN G LON DO N STOCKISTS OF YAESU AN D ICO M EQUIP ME NT Full ranges in now, including these models rin» YAESU FRG-7000 ICO M IC-240 YAESU FT-225R D

PHO NE FOR DETAILS OF CURRE NT STOCKS-NE W AN D SEC O N DHA N D. CLOSE D W E D NES DAY

•1 EASY TER MS UP TO CRE DIT SALES m o INSTA NT HP FOR

3 YEARS 4111 L BY TELEP H O NE VI 11SA LICE NSE D AM ATEU RS

So easy for Overseas Visitors -just seven stops fro m Heathro w

2 N O R T H FIEL D R O A D. E ALIN G, L O N D O N W 1 3 9S Y. Tel: 01-579 5311

G2 B S W IN D E X T O A D V E R TI S E R S REG. WARD & CO. LTD • G8 C A YAESU ABC Electronics (Oldham) Ltd .. 550 KW Amateur Radio Products .. 545 K.W. 103 VSWR Meter and FT101E Transceiver £485.00 Acto & General Supplies . 543. Lee Electronics . .. 539 combined Power Meter £23.00 F12008 Transceiver and AJH Electronics . .. cover iv London Communications . 552 107 Combined E-Z Match. FP200 PSU £330.00 Amateur Electronics .. .. 478/9 Lowe Electronics 474/6 VSWR and RF Power Yaesu 301D all solid state Amateur Radio Bulk Buying Microwave Modules Ltd .. 482 Indicator. Dummy Load £585.00 Group . • - Covet ii MK Products .. • . 545 and Antenna Switch for FR101 S Receiver £372.50 FR101 D Receiver £465.00 Amateur Radio Exchange .. 551 Modular Electronics . 549 3 outlets £108.00 KW Dummy Load. son YD844 Desk Mic £18.00 Amateur Radio Shop . 545 Mosley Electronics Ltd . 530 (encased with S0239) £20.00 YD846 Hand Mic £7.50 Ambit International .. 540 & 546 Wm. Munro (lnvergordon) Ltd 473 Trap Dipole Co-axial YH55 Headphones £8.00 Amcomm Services 469 8i 543 Nunsfreld House Community Feeder . £26.60 SP101B Speaker £15.00 B. timber .. 556 Group . .. 550 3-way Antenna Switches Y0100 Monitorscope £145.00 B.B C . . . 553 Park Electric Co Ltd .. 550 (for co-ax) .. £7.50 FT221 £339.00 £144.00 Booth Holdings Bath .. .. 544 Partridge Electronics Ltd . . 542 SHURE MICROPHONES New G/C Receiver FRG 7 Model 444 £26.26 S.E M. 2-match £32.00 Eiredhurst Electronics .. .. 546 PM Electronic Services .. 538 Model 201 £9.50 Burns SCS . 548 Polar Electronic Developments 542 Cambridge Kits . .. 544 0M70 Electronics Ltd 543 A//above prices plus VATat 72%. NB- 'Test Equipment'. VAT at 8% includes SWRIPWR meters and dummy loads. Catronics Ltd . Cover ii Radio Shack .. 465 RT & I Electronics .. 546 CB Electronics .. 542 USED EQUIP MENT C & C Electronics .. . 548 RIP Electronics . . 543 KW201 Ra and handbook, with external Heathlut -0" multiplier. £130.00 Chase Electrics Ltd 550. SEM Electronics .. 541 Harry Collins .. . .. 540 South Midlands AGENTS FOR G2DY M ANTI-TV ANTENNAS. AND BALUNS Datong Electronics . 547 Communications Ltd 462/4 & 554 Valves lar Yaesu, etc, 6E126, GU8. 610:36. 12AX7A, 1213Y7A, 12AU7, 6JS6C. Ferranti Ltd .. .. 555 Spacemark Ltd 506 6146. 6HF5. SLOE, 6EA8. EGKE, 61468. 6K06. RCA Valves for KW Garen Electronics .. 546 Stephens James Ltd . 535 equipment etc G2DYM Aerials 538 T D. Services . 547 Sentinel 2m Preamps and 2m convertors/Europa transveners, .1 Beams and GW M Radio Ltd . 544 Thanet Electronics . 470/2 Stolle rotators 140. 14g ant wire, insulators. 52 & 75 ohm co-ax, and UHF L Hardie .. 547 IMP Electronic Supplies .. 545 plugs, sockets and reducers. G.Whip mobile antenna. %Nightcaps, Mast Couplers Hy-Gain verticals. SWR 10 (Twinmeter). SWR/PWR Meters Hartley Crystals . .. 547. Trainee, Communications Ltd .. 554 AMTRON KITS Heath (Gloucester) Ltd .. 549 TYCOte International Ltd .. 552 TRADE INS WITH PLEASURE, OUR STOCK OF GOOD SECOND-HAND Heller Electronics .. .. 535 Reg Ward & Co Ltd . 551 EQUIPMENT CHANGES DAILY-LET US KNO W YOUR REQUIREMENTS D. P. Hobbs Ltd .. .. 544 Waters & Stanton Due to currency fluctuations prices of imported equipment are liable to Integrated Circuits Unlimited 477. Electronics . . 466/8 alteration Interface Quartz Devices Lid 540 Western Electronics (UK) Lid 480/1 ADD 1206 VAT to all prices except used equipment HP TERMS AVAILAELE CARRIAGE EXTRA ON ALL ITEMS James & Martin Ltd . 550 W H Westlake . 5 ACCESS/BARCLAYC AR D Johns Radio . . . 538 Yaesu Musen Co Ltd 5364/7 AXMINSTER, DEVON EX13 5DP Telephone 33163

RA DIO CO M M U NICATIO N June 1978 551 CLASSIFIED ADVERTISEMENTS

Private advertisements 15p per word, minimum £3.00. Trade advertisements 25p per word, minimum £5.00. Box Number 76p extra to wordage or minimum. Semi-display 1/12 page of x 3") (35 x 76mm) £21.00. 1/16 page (i" x 3") (22 x 76mm) £15.00. Please write clearly. No responsibility accepted for errors. Latest date for acceptance-1st of preceding month. Opportunities All classified advertisements must be prepaid. Copy and remittance to: C. C. LINDSAY. 2 Leyburn Gardens. Croydon CRO 5NL. Tel: 01.686 5839. Me mbers' Ads must be sent to the Editor at Chelmsford. in FOR SALE Electronics

CISL CAR DS, printed to your own specification on white gloss cards. Tycoate International manufacture Send SAE to Caswell Press, 11 Barons Way. Woodhatch. Reigate, powder coating plant for a wide range Surrey. of industries. These include complete CISL CAR DS, LOGBOOKS. Samples 9p. Beauprint (G30YI) "Turnkey" installations and a range of Meltham Road. Honley. Huddersfield. G.I. AMATEUR SUPPLIES GI3ZIA for Trcyrs, Rs Tx, Antennas. wet paint and powder application Mies, etc. Trade-in's welcome. Large stocks at 10 Church Street. equipment. Applications are invited for Enniskillen, N. Ireland. Tel: (0365) 22955. the following appointments:. RSGB PUBLICATIONS, Maps, Charts, Sundries. etc. Les Hawkyard. G5OH, 100 Shirley Street, Southampton SO1 4FB. Tel: 773378, 9-5.30 weekdays. Electronics Engineer ULTRA CUB. High band FM 0.5W, 2-channel portable Tx/Rs with Responsible to the Services Manager for mic/LS and case. Less battery and antenna. Ideal for conversion to 2m, £27.00. No circuits. Storno and GEC FM base stations and some 70cm developing processor control systems, gear. SAE for details. G8AKA ClTH R. Reading 332582. with special emphasis on process plants. • OSL and LISTENERS CAR DS. We offer a range of styles and prices Experience in logic is necessary, with on quality cards and at short delivery. SAE for samples. G3VZF. 5 The Close, Radlett. Herts. HND as a minimum qualification. TR3200 with popular channels, 2 extra rubber-duckies and a mobile mount, £180. TR2200 GX with rubber-ducky and mobile mount, £130. G4DA W. OTHR, Northampton 714821. anytime. 2 Electronic Service K W2000A. good condition. £160. 3-4000Z linear complete, £75. 1100V Trany large. £10. Large electrolytics, write details, 7 Arundel Engineers Road, Coventry. To be based in Northern Home Counties HB9CV 2M and 70cm BEA MS, Mk11 improved version only £5.50 and in Skelmersdale. Experience inc carriage. Also superior aerial wire. 20svvg. copper plates, steel core, PVC ins., only 4p per metre + 2f3 metre carriage. Details, Amtest, 55 necessary. Company cars provided. Vauxhall St. Worcester, WR3 9PA. Attractive salaries, commensurate with experience and ability. Non- contributory pension scheme. Free life assurance. WANTED Please apply in handwriting, clearly indicating the position applied for, and GO OD SEC ONDHAND EQUIP MENT AL WAYS W ANTED. giving details of present and previous Come to Amateur Radio Exchange for the best deal. 2 Northfield Road, employment, to Ealing. London W13, Tel: 01-579 5311. The Personnel Officer, Tycoate International, SITUATIONS VACANT Gardiners Place. West Gillibrands. Skelmersdale, Lancashire WN8 9SP.

WE PAY TOP SALARIES "Turnkey" powder or liquid FOR THE RIGHT ENGINEERS Starting at f4000 p.a. for Bench finishing plant. Engineers Increasing rates for Field Service Engineers The all-in system from Tycoate. London's largest independent radio-telephone company is expanding fast! We have built a reputation for reliable efficient service. If you have the capability we need you urgently. Kno wledge or experience of mobile VHF equipment is what we're looking for. Call Mike Rawlings or Bill Clarke on 01-328 5344 NO W I London Communications tfOèoate (Equipment) Ltd 30 Boundary Road, London NW8 01-328 5344 internanonal

552 RADIO COMMUNICATION June 1978 TECHNICAL ASSISTANTS TRANSMITTER DEPARTMENT

We have vacancies for Technical Assistants to work as members of engineering teams based at Radio, Television Transmitting Stations throughout Great Britain. These staff will be involved in the operation and maintenance of a wide range of transmitting and receiving equipment. They will receive full time training, successful completion of which they will qualify internally as BBC Engineers and will have received a BBC certificate. Applicants, male or female, should be aged between 18 and 26 and have normal colour vision and hearing and a good general education offering '0' levels (grades A, B, or C) in English, Mathematics and Physics and have read up to 'A' level in Mathematics and Physics. Alternatively an ONC or Part 1 of the City & Guilds TTC. (No. 271) would be acceptable. Candidates should have a relevant practical interest in transmission or electronic techniques and be able to demonstrate their ability to apply their knowledge of electrical principles to practical problems. Salary: Depending upon experience will be in the range of £2,500 -.£2,720 p.a. Additional payments may be made for shift working irregular hours and overtime. For further details and application form write to The Engineering Recruitment Officer, BBC Broadcastin g House, London W1A1AA quoting reference No. 78.E.(TX)4042/RC and enclose an addressed envelope at least 9" x 4." Closing date for completed application forms is 14 days after publication. o

RADIO COM MUNICATION June 1978 553 SERVICE,SALES INTERESTED IN ENGINEERS LOGIC? As a consequence of our continued and successful expansion in the retail and wholesale fields of amateur communications we If you are, and can put together TTL and CMOS are, once more, looking for new staff. chips in such a way as to make them do something In addition to a sound general knowledge of communications useful, then you could be the Development Engi- equipment; neer we need. Sales Engineers—should have a good knowledge of modern Our product range includes micro-processor amateur equipment: preferably with some experience in the controlled, electronic teleprinters, so an interest in retail/wholesale trade. RTTY could be an advantage. Formal qualifications are not as necessary as Service Engineers—should have either considerable practical experience of servicing electronic equipment, or appropriate natural ability and imagination. technical qualifications. If you want the chance to work with micro- The ideal candidates will be licensed amateurs, be keen to work processors and use your experience gained in at their hobby, havea spirit of willing co-operation and a desire to Amateur Radio construction then ring us on Slough maintain our high standard of service and customer relations. 26955 and ask for Chris Payne. We are looking for enthusiastic, cheerful, hardworking people Salary up to £5K. who would enjoy being part of an extremely busy "go-ahead" company.

TRANSTEL CO M MUNICATIONS Please apply in the first instance by telephone to HQ at Totton (04216) 7333 LIMITED MILL STREET. SLOUGH SL2 5DD South Midlands Communications Ltd Osborne Rd, Totton, Southampton, Hants SO4 LIDNI

/ Tick as ME MBERS' AD ORDER FOR M FOR SALE E W ANTED (appropriate)

• See Me mbers' Ads page for conditions of acceptance. • Not more than 40 words, including name, address, etc • Do not forget 75p remittance plus wrapper. • Please write in block capitals, or type. • Use correct address

Licensed members are asked to use their callsign and 13THR. meaning that their address in the current RSGB Amateur Radio Call Book is correct BRS and A members will, of course. have to provide their name and address.

I enclose cheque/PO for 75p to cover the cost of this advertisement.

Signed

Date

554 RADIO COM MUNICATION June 1978 Electronics Research ancT Development with Ferranti

Expansion and re-organisation within the proven design experience with low power Aircraft Equipment Department has created a circuits, A knowledge of the use of number of interesting positions in the R 8, D microprocessors would be an advantage. - laboratories at Bracknell. Ref :A/175/ RC The Department which isactive in both Civil The a bove positions are open to professionally Aviation and Defence fields, with airborne and qualified Electronics Engineers. ground based equipment: covers a broad range of act ivities extending from medium/high IN ADDITION we have a number of power electronics to work with low power other interesting vacancies for candidates of microcircuits. graduate experience. The following positions have arisen: These posts should be regarded as stepping stones to higher positions within a technically SENIOR ENGINEER to lead a orientated company. Highly competitive small group associated with light current salaries will be paid. The laboratories are equipment. The candidate should have at least located in a pleasant manor house situated on two years experience in industry with a good the outskirtsof Bracknell. knowledge of signal processingand use of digital techniques in the communications Application forms may be obtairied by writing field. Ref: A/174/ RC to Mrs. J. Hunt, Ferranti Limited, Lily Hill SENIOR ENGINEER to work with House. Lily Hill Road. Bracknell, Berkshire, or control systems. The candidate should have telephoning Bracknell 24001 ext. 8. FERRANTI Selling technology

RADIO COMMUNICATION June 1978 555 TER MS OF BUSINESS: CASH WI TH OR DE R, MI NI M U M OR DER OF £2.00. B. RAMER ELECTRONICS ALL PRICES NO W INCLU DE POST & PACKIN G (UK ONLY) CALLERS WELCO ME by APPOINT MENT ONLY DEPT RC, S STATION RD, LITTLEPORT, CAMBS, CB6 IQE Please enclose stamped addressed envelope with ALL Enquiries TEL: ELY (0353) 860185 (TUESDAY-SATURDAY) IPLEASE ADD VAT AS SHO WN PLEASE ADD 8% VAT (except where shown) PLEASE ADD 8% VAT (except where shown) LARGE ELECTROLYTIC PACKS.Contain range of VIDICON SCAN COILS (Transistor type, but no DIECAST BOXES (APPROX SIZES) large electrolytic capacitors, low and high voltage data) complete with vidicon base £6.50 each Brand 4.3" 2.3" .1.2" (111 60.30mm) E1 10 types. over 40 meces. £3.00 per pack (+ 121% VAT) new '4.8 - x 2.3« x 1.5' (121 . 60. 38mm) 1.65 4.8' 3.8- .1" (121 rs95s 25mm) 1 90 BSR AUTOCHANGE RECORD PLAYER DECKS SPEAKER CABINET TYPE M321 4.8 - 3.8" x 2" (121 . 95 .51mm) 2.20 with cue device. 33--45-78RPM. for 7-, 10" and 12" 6.8".4.8" x2" (171 x121 51mm) 2 75 records Fitted with SC12 M Stereo Ceramic car- White matt finish wood cabinet with white sprayed 4.8 3 8- .3" (121 .95.76mm) 3.00 tridge and styli. Brand new £14.00 +121% VAT_ cloth grille, 9" x 9" x 41 - deep, containing 61" dia, 6.8" x 4.8" x 4" (171.121 101mm) 4 20 GARRARD AUTOCHANGE RECORD PLAYER 15ohm full range speaker. with 100V line transformer. 8.6" s 5.8" x 2- (222 x 146 ir 51mm) 3.75 DECKS. Model 6.300. with cue device. £4.50 each or 2 for £8.00 + 121% VAT 10.6" 6.8" x 2" (273.171 51mm) 4.85 33-45- 78R PM, for 7", 10' and 12" records Fitted RED LEDs (Min type), 5 for 76p. with KS41B Stereo Ceramic cartridge and styli. GLASS BEAD FEEDTHROUGH INSULATORS, Brand new £16.00 -1296 VAT 8-TRACK CARTRIDGE PLAYER UNITS solder •in type, overall dia. 5mm, pack of approx. 50 Please note, record decks sent by Roadline. allow 14 for 50p. , days for delivery. with internal mains psu and 25 watt mono amplifier (100V line). To play standard 8-track cartridges. All LARGE GLASS BEAD FEEDTHROUGH INSU- 10.7MHz SSB XTAL FILTERS (2.4kHz Bandwidth) contained in a smart veneered wood cabinet, size LATORS, as above but 8mm die., pack ol approx. 50 Low imp type, Carrier and unwanted sideband approx. 14" wide x 53" high is 11" deep. Supplied for 70P. reiection min. -40dB, (need 10.69835 and with circuits Brand new and boxed. SPECIAL OFFER 10-70165 xtals for USB/LSB, NOT SUPPLIED). BOX OF P. C. BOARDS. mixed PCBs. containing £35.00 each + 12;96 VAT Size appro. 2' r r . 1" £10.00 each Transistors. ICs, Resistors, Capacitors, etc. Good LOW PASS FILTERS (low imp. type) 2-9MHz. small breakdown value. Our selection £3.00 per box metal encapsulation, size approx. 11" x 2" x r SEMICONDUCTORS SLIDER SWITCHES, 2 pole make and break (or can 75p ear h. BFY51 Transistors. 4 for 609. be used as 1 pole change-over by linking the Iwo BYX 38/300 Stud Rectifiers. 300V at 2.5A. 4 for 609. centre pins) 4 for 50p. TUNED COILS. 2 section coils. around 1MHz, with a BCY72 Transistors. 4 for 60p. SMITHS CLOCK MOTORS. 200-250V 50Hz 2 black smart tuning knob. which moves an Internal BSX20 (VHF osc/mult.) 3 for 60p watts, 1 Rev, every 2 mins, 3 hole fixing, 1" spindle. core to vary the inductance, many uses, easily BC108 (metal can) 4 for 50p. £1.00 each rewound, 3 for 60p. PBC108 (plastic BC108) 5 for 50p. SLO W MOTION MOTORS. 120V 50Hz I rpm. Size approx 2" cha, 11" deep, with 4- spindle. 809 each or FULL RANGE OF BERNARDS/BABANI ELEC- 13F152 (UHF amp/mixer) 3 for 50p. 2 for £1.00. TRONICS BOOKS IN STOCK. SAE FOR LIST. 2N3819 Pet. 3 for 609. 8C148 NPN SILICON. 4 for 50p. SUB-MINIATURE ROTARY SWITCHES. 4 s 5 A NEW RANGE OF SPEAKERS & CABINETS. 8C158 PNP SILICON. 4 for 50p. way make contacts. Size approx. dia, 1' deep. rii" BRAND NEW & BOXED. AT BARGAIN PRICES. BAY31 Signal Diodes. 10 for 35p. r spindle. 50p each CELESTION 8- . 5- ELIPTICAL SPEAKERS. 741CG RCA OP-AMPS. 4 for £1.00. IN4148 (IN914) 10 for 26p 20ohm. 3 watts rated, £1.50 each 121% VAT. UR41 ATTENUATION CABLE, Nominal 72ohm. BC107 (Metal can) 4 for 509 TYPE 1,2 TRIANGULAR CORNER CABINETS. overall dia. approx 1" Alt per 10011 100MHz SCRs 400V at 3A, stud type. 2 for £1.00 Smart woodgrain Formica type finish with nylon 218dB, 200MHz 316d8, 600MHz 449dB, TIP2955 Silicon PNP power transistor 60V at 15A. grille Overall height 23' x 12" wide. Contain 3000MHz 625d8 Ideal for Rx or Low power Tx fixed 90W, Flat pack type. 2 for £1.50 Three 15ohm 4' Full range speakers in attenuators Supplied with attenuation graph. 4 GERMANIU M DIODES. appro. 30 for 30p. parallel + 100V line transformer (easily discon- metres for £1.00. nected for 5ohm operation). £7.50 each (or 2 for OSMOR REED RELAY COILS (for reed relays up to SOLDER SUCKERS (Plunger type) £14.00) 4-12 e, VAT. r dia, not supplied) 10V. 1Kohm coil, 2 for 509. Standard Model £5.50. TYPE M704 CEILING SPEAKERS. White plastic MIXED COMPONENT PACKS. containing resis- Skirted Model £6.00. fascia 10" square. for recess mounting into ceiling, tors, capacitors, switches, pots. etc All new, and Spare Nozzles 60p each with 8" dia. 15ohm full range speaker. £4.00 each hundreds of items. £2.00 per pack, while stocks last MULTICORE SOLDER + 121% VAT. 4Kg (1 11b) 60/40. 20SWG on Plastic Reel, £3.00. TYPE L4 PORTABLE SPEAKER CABINET. Smart PLUGS & SOCKETS WELLER TCP2 and PU2D PSU. Temperature con- woodgrain Formica type finish with nylon grille, N-TYPE PLUGS 50ohm 609 each. 3 for £1.50. trolled soldering iron, with matching Power Supply 15" high . 14 - wide s 7-deep (tapering). Greenpar (GE30015) Chassis Lead Terminators Unit, containing sponge and spring stand £30.00. Containing 10" round, 15ohm full range speaker (These are the units which bolt on to the chassis, the 4. 100V line transformer. £7.00 each +12 % VAT. lead is secured by screw cap, and the inner of the SPIRALUX Tools for the Electronic enthusiast.. TYPE HT4 HOTEL SPEAKER CABINET. Wood coax passes through the chassis). 30p each. 4 for SAE fur list. veneered, 122" wide 51" high s 3.1 - deep, with £1.00. aluminium grille +volume control and 4 way + off PL259 Plugs (PTFE) Brand new, packed with re- MAINS TRANSFOR MERS, TYPE 15/300 240V switch panels on front. Very smart, Contains 3ohm ducers, 75p each input. 15V at 300mA output, £1.50 each. 5' . 3" eliptical speaker + 100V line transformer. $0239 Sockets (PTFE) Brand new (4 hole fixing type) MAINS TRANSFOR MERS TYPE .15/100:240. 220. £5.00 each + 121% VAT 60p each 110. 20.0V input, 45V all00mA output £1.50 each VALVES MECHANICAL COUNTERS. 4 digit Resettable, 60p A NEW RANGE OF QUALITY BOXES each &INSTRU MENT CASES. OCV03/20A (ex equipment) £3.00. Aluminium Boxes with lids. OCIV03/10 (ex equipment) 759 or 2 for £1.20. AB10 5 is 4. 11 75p 6BH6 (ex equipment) 2 for 50p. ALL BELO W -ADD 12e/0 VAT AB13 6 s 4 ir 2 £1.00 All the above valves are untested. except for heaters VARICAP TUNERS Mallard Type ELC1043/05 AB14 7 . 5 x 2 £1 .25 and no guarantee of percentage of emission is given. Brand New. £5.00 AB15 x 6 3 el.50 Sorry no returns TV plugs (metal Type) 4 for 50p. AB16 10 u 7 x 3 £1.75 MU LLARD 85A2 85V STABILISER VALVES 3 pin Don plugs, 4 for 5Up. AE117 10 x 41 x 3 £1.50 (brand new) 70p each or 2 for £1.20. Din 3 pin Line Sockets, 15p each AB25 6 s 4 s 3 £1.25 6BW6 VALVES (BRAND NEW), 85p each or 2 for Din Sockets 5 pin. 270 deg. 4 for 50p. Vinyl Coated Instrument Cases. E1.50. Din Speaker Skts. 2 pin, 4 for 309. Blue Tops and Plain lower sections. Very smart finish HF CHOKES wound on 1" x 1" long ferrites. 4 for RESISTOR PACKS, appro. 300 pieces. j to 2W W81 5 . 21 ir 21 76p 50p. types mixed values, our selection £1.00 pack WB2 6 . 4; x I; £1.35 VHF CHOKES wound on 6-hole tubular ferrites. Slot ELECTROLYTIC CAPACITORS WB3 8 x 5 x 2 £1.80 40p. Dubillier Electrolytics. 50pF. 450V. 2 loi 50p. WE14 9 x 53 ir 21 £2,00 DUAL TO18 HEATSINKS 1" x x r wah screw- Dubillier Electrolytics. 100e, 275V. 2 for 50p. WB5 11 is 63 . 3 £2.26 in clamps. 3 for 50p. Plessey Electrolytics, 470).iF. 63V. 3 for 50p. WB6 11 x 7; .31 £2.50 - TCC Electrolytics. 1000pF 30V. 3 for 60p. WB7 12 n 53 s 5-1 £2.85 AE1 CS10B/R MICRO WAVE DIODES: up to %- Dubillier Electrolytics. 5000mfd at 35V, 50p each W8353 8 .5 ri 3 £2.25 Band, max noise figure 8•5c18 at 9375GHz. .80p each Dubillier Electrolytics. 5000uF at 50V. 60p each PLASTIC PROJECT BOXES with screw on lids (in ITT Electrolytics. 6800mfd at 25V, high grade, screw Black ABS) with brass inserts. BARGAIN PACK OF LOW VOLTAGE ELEC- terminals, with mounting clips. 50p each Tyne N81 appro. 3" . 21" x 4Sp each TROLYTIC CAPACITORS. Up to 50V working Type N62 appro. 31" . 2e» rs 11" 55p each Seatronic manufacture. Approx. 100 £1.50 per pack A LARGE RANGE OF CAPACITORS AVAILABLE Type N B3 appro. 41" ir 3) - x 1i" 85p each ( + 121% VAT) AT BARGAIN PRICES, SAE FOR LIST.

556 RADIO COM MUNICATION June 1978 PUBLICATIONS OBTAINABLE FRO M RSGB RSGB me mbers can obtain a 10 per cent discount on the puces listed below at the lime of ordering (excluding Ham Radio Magazine and Ham Radio Horizons) TO obtain the discount. deduct 10 per cent, calculated to the nearest penny from the total value of the order (using the tees! price list) and enclose a remittance for the balance Also enclose an address label hem a recent Radio Communication wrapper as proof of membership

RSGB PUBLICATIONS OTHER PUBLICATIONS Technical books American Radio Relay League Amateur Radio Awards £2.15 Antenna Book (13th edn) €3.86 Amateur Radio Techniques (6th edn) £3.95 Course in Radio Fundamentals . . £2.96 Guide to Amateur Radio (17th edn) £1.71 FM and Repeaters for the Radio Amateur. £3.09 Morse Code for Radio Amateurs . 54p Solid state Design for the Radio Amateur . £5.80 OSCAR-Amateur Radio Satellites . £4.20 Hints and Kinks ...... £2.37 RSGB Amateur Radio Call Book 1978 £3.21 Radio Amateurs' Handbook 1978 (Paperback) £7.30 RAE Questions and Answers . . . . £2.00 Radio Amateurs' Handbook 1978 (Hardback) . £10.21 Radio Amateurs Examination Manual (7th edn) £1.60 Ham Radio Operating Guide £3.19 Radio Amateurs» Examination Revision Notes . 86p Single Sideband for the Radio Amateur . £3.52 Radio Communication Handbook 5th edn, Vol 1 £9.36 Getting to know Oscar from the ground up £2.46 Radio Communication Handbook 5th edn. Vol 2 £8.12 Specialized Communication Techniques . £3.19 Radio Data Reference Book (4th edn) £3.65 Understanding Amateur Radio . £3.65 Service Valve and Semiconductor Equivalents . 48p VHF Manual £3.74 Teleprinter Handbook . . . . . £8.89 Electronic Data Book . . £3.20 Test Equipment for the Radio Amateur (2nd edn) £4 42 TVI Manuel (Out of print) VHF UHF Manual . . . £6.82 Radio Amateur Callbook Inc World al their Fingertips (Paperback) £1.63 American Callbook (USA listings) 1978 . . £9.75 American Callbook (DX listings) 1978 . . World at their Fingertips (De-luxe) • £2.76 £9.98 World Atlas (Amateur radio prefixes) £1.75

Log books Radio Publications Inc Standard Log . . . £1.55 Beam Antenna Handbook £3.90 Receiving Station Log £1.54 Setter Short Wave Reception (3rd edn) . . £3.42 Mobile Mini-Log £1.09 Cubical Quad Antennas . • . . . £2.77 De- luxe Log f 3 16 Simple. Low-cost Wire Antennas (out of stock)

Maps, charts and lists Miscellaneous Countries List, HF Awards List . 25p Amateur Television . . . . • £2.20 Great Circle DX map (in tube) £1.29 Complete Handbook of Slow-scan TV . • £5.58 Oscar map lin tube). . . . 43p International VHF FM Guide (Out of stock) 0TH Locator map (Western Europe) (in tube). £1.15 RTTY the Easy Way . . . . £1.02 0TH Locator map (Western Europe) (on card) 57p Radio Amateur Operators Handbook £1.11 UK Beacon List . . . . . 19p Radio Valve eir Semiconductor Data . £4.00 UK Repeater List . 19p 80- meter DXing £2.86 IARU Region 1 Beacon List 19p M ORSE INSTRUCTION AIDS Me mbers' sundries G3HSC Rhythm Method of Morse Tuition-- Cailsign lapel badge (5 weeks delivery) . . . £1.60 Lace' badge (RSGB or RAEN emblem, pin fitting) . 51p Complete Course (two 3-speed 1p records and one ep record plus books) ...... £5.601 Tue (Maroon or Blue) £1.96 Beginners Course (one 3-speed (p record and one Radio Communication Easibinder £3.00 ep record plus book). . . . . £4 . 121 Car window sticker (RAEN or RSGB) (self -ad . 31p Beginner's 1p (0-15 wpm) plus book . . . £3.441 Members' headed notepaper (50 sheets) quarto . 85p Advanced 1p (9-42 wpm) plus book . . £3.441 Members - headed notepaper (50 sheets) octavo . 60p Three-speed simulated PO test lin ds ep record £1.151 Radio Communication back issues (as available) • 84p Overseas orders add Cl 12 RSGB contest log sheets (100) 77p RSGB teeshirt (large, medium or small) . £2.25 M AGAZINE SUBSCRIPTIONS Prices include postage, packing and VAT where applicable For air OST (including AR R L membership) (Per annum) . £9.25 mail despatch, please ask for price before ordering Goods are Subscriptions for OST should be sent to RSGB, 35 Doughty Street. obtainable less p 8r p. at RSGB headquarters between 9.30am and London WC1N 2AE 5pm Monday to Friday

POSTAL TER MS. Cash with order Stamps and book tokens Ham Radio Magazine (per annum) (incl air cannot be accepted Cheques and postal orders should be crossed delivery) . . . . £14.00 and made payable to -Radio Society of Great Britain" Giro A/C No Ham Radio Horizons £6.00 533 5256 Subscriptions and changes of address for Ham Radio All overseas orders add C1 to cover insurance if required Magazine and Ham Radio Horizons should be sent to : Ham Please write your name and address clearly on the order Radio Magazine (UK). PO Box 63. Harrow. Middlesex HA3 6HS ORDER FRO M:

RSGB Publications (Sales), 35 Doughty Street, London WC1N 2AE A. J. H. ELECTRONICS Proprietor: A. J. HIBBER D (G8ACIN) Tel RUGBY daytime 76473. evening 71066 Terms of Business: Cash with order. Mail order only. or Callers by appointment S A E. with enquiries Handling Charge 40p Minimum order £1.00. Official orders accepted on a strict monthly basis. Prices no w include VAT FULL MO NEY-BACK GU AR ANTEE ON ALL ITE MS "KENT" MODULES PROFESSIONAL GRADE MODULES NO W AVAILABLE TO THE AMATEUR 10.7 MHz NARRO W BAND F.M. 2WATT AUDIO AMPLIFIER I.F. AMPLIFIER WITH SQUELCH PERF OR M AN CE Sensitivity - 4pV (EMF from a 50ohm source) for 20db PERF OR M AN CE quieting Po wer Output - 2W minimum into 40<10% distortion Selectivity - _t 711(Fiz @ 3db, ±25kHz @ 60db. Sensitivity - 75mV p-p @ 1kHz for full output A.F. Output - 200mV p•p when input is above limiting Band width - 200Hz to 15kHz threshold and modulated ± 5kHz @ IkHz. Squelch - noise operated, threshold adjustable over the - 75uS de-emphasis range 0 to 20db s/n - Output 3db down @ 4kHz• 20db down Cri Supply - 9 to 15 volts D.C. e 7mA quiescent (neg. 8kHz (de-emphasis removed) earth) - Noise output to suit squelch circuit on A.F board FEATURES Supply D.C. 9 to 15V @ 30mA (negative earth) True noise operated squelch with adjustable threshold, no hysteresis FEATURES Will drive a wide range of speaker impedances, 4 to 160. Thermal High sensitivity and selectivity overload and short circuit output protection. On board crystal filter buffering for ease of interface Rectified and filtered squelch output available for channel scanner Single Conversion. etc. Audio low pass filter to remove unwanted high frequency noise Small size only 52m m x 52m m "S - meter and delayed AGC outputs Small size only-97 x 42m m PRICE £26.50. inc. VAT PRICE £9.50 inc VAT NOTE TO ALL FT101 OWNERS: * * * ** NO W AVAILABLE ***** FM IF AM PLIFIER for the world famous FT101 ready built into a small die cast box-just plug the leads into the back of your FT101 and remove one wire from the function switch. Contains crystal filter for superb performance-price £38.00. Next month a 2 meter convertor with matching 6 channel oscillator unit, these used in conjunction with. our FM IF amp and audio board will make a first class monitor receiver with a sensitivity of better than 02 pV. ALL MODELS FINISHED TO PROFESSIONAL STANDARDS AND FITTED WITH MOUNTING BUSHES

PROFESSIONAL GRADE CO-AX RELAY made by THREE-GANG TUNING CAPACITOR 365 pf per JACKSON BUTTERFLY TRIM MERS 17, 17PF SIVERS LAB Sweden We have no data on these but section direct drive 75p each. 1.2rnm air gap Cat No C713. 50p each, a few with I". the following figures were obtained with tests at CATHODEON 1 .4MHz CRYSTAL FILTER 10 spindle. 65p each 1 2GHz insertion loss =1 db. isolation - 70 db. base, for lower side band SSB. with base con- ELECTRONIC:IMES TUNING DIALS reduction 6-1 fitted with "N" type sockets and operates from 24 01 nections new unused £4.00 each, two for £7.00. and 36-1. uses epicyclic drive. moulded clear plastic 48 volts DC. contacts must be rated at well over Disc ceramics 0-01 Mi 2.5Ky working 5p each 1000 pl front. size 100mm u 160mm. supplied with two 500 watts e 500MHz brand new for only £15.00 500 vw 10 for 15p. scales and two pointers. £6.50. few only so order now WIMA MINIATURE POLYESTER CAPACITORS STEREO CAR CASSETTE player amplifier boards CO-AX CABLE type UR57 75 ohm 10mm dia only 2•2 size only 6mm sou 2mm thick. PC mount pin with two amp ICs NEC•uPC 1001 H2. some models db loss > 145MHz. 4.2 db loss 432MHz (both spacing 5mm 100 vw in the following values 1000 with uPC 1025H. requires 12V DC. 31W per figures quoted per 10011.). Due to large purchase we pi, 2200 pf. 1500 pf. 10 for 20p or 3p each channel, removed from new equipment by manufac • can offer at a very low price of £12.004- £2.00 CO-AX PLUGS 50 ohm "N" type right angle for UR67 lure,. size 120mm u 45mm, supplied with circuit. carnage per 100 yard drum Brand new and unused £1.00. P1259 right angle for UR57/67 etc. £1.00. £2.25 each PYE FUNCTIONAL TEST SET type TS2 made for S0239 sockets 4 hole fixing 50p. 50 ohm BNC FM RADIO FRONT END TUNER Units 88-108MHz testing the COM PAC 8 HF SSB packset contains the right-angle adaptors 50p. SPECIAL OFFER 75 ohm (remove three Cs and it tunes Air Band) and 2m very following circuitary --audio oscillator, noise gene- BNC plugs and single hole sockets 35p each high quality and stable unit with exceptional sensi- rator audio amplifier, battery load. RF dummy load. MINIATURE NIXIE TUBES ITT-5853S with left tivity FET RF amp NPN mixer and sepaime osc. .AFC. and AGC inputs, works from 9-15V D.C., with etc. Fined with nice miniature 500 pA•meter by and right hand decimal point size only ru circuit, new and unused BARGAIN @ £3.30 each: Sil am, multiway switch. mic insert etc., built into die nominal working voltage 170 volts DC, new unused cast case size approx 9' u r 2" These are brand 5 for £2.50p 10 for £4.509. 470K Hz AM IF AMPLIFIER BOARDS as used in Car Radio/Cassette players full of miniature Rs & Cs new and boxed at only £5.00 each (the meter must DECADE COUNTER PCB made to suit the above be worth this price) supplied with circuit. nixie tube also takes 5N7490. 7475, and 7400 ready two double tuned IFTs, trimmers, coils, tantalum Cs. transistors. and LM382N low noise stereo pre • amp. TRANSIPACK STATIC INVERTOR type drilled etc, 75p each, set of 5 £3.40. IV5350/24/240/250/50. input 24 volt DC output TRIM MER CAPACITORS 10mm dia. ceramic, 2- size 1r u rir new unused no info £1.00. 240 volt AC 50 cis 250VA. these are brand new 8pf, 3.10p1. 4.20pf, 10.40p1, all 10p each FIEVCO VHF AERIALS MA200 Magnetic base with unused £80.00. (2 only). Buyer to collect by 7mm dia. ceramic. 3-9pf. 7-35p1. an 10p each Ilth 144-146MHz coil & whip appiox 3db gain arrangement Tubular ceramic. 1-60 solder in type. Sp each. 60p £19.00 p/p f 1 00 VALRADIO TRANSVERTOR type 0241500S 24 for 10 REVCO 144-146MHz 11th mobile aerial £8.50 also volt DC input. output 115/230 volts AC 50Hz 500 Mullard tubular ceramic i38.6.8pf bolt in type. 159 commercial R/1. band 156-172MHz (approx 3db watts new unused £75.00 (two only) Buyer to each Ceramic miniature compression P C. mount gain both types) £8.50. collect by arrangement 10-400. 8p each 500p.A small Jap type 45p each LEATHER CASES FOR SF1 Starphone new unused Plastic semi-airspaced 2-25p1 10mm dia 6p each: CRYSTALS OK for 2 Mtrs le-- 4 10 7MHz. 335, £2.75. 10 for 50p. 33,550 33,575. 33.600. 33.675. 33,700. 33.725, PVC WESTMINSTER POWER LEADS W15 Oxley airspaced 9mm sq base 1 .10pf and 1 .150, 33.750. 33.775 33.800. all £1.25 each. AM/FM etc. wired for positive earth, with in•line 18p each. 2-30pf 20p each SECOND CONVERSION CRYSTALS 11 170 H MI), 11 155 HC6, U. 10230 HC6/U & 1-1C18/U. fuse holder new unused £2.50 Erie teflon tubular trimmers "530 series" 0-25-1 5pf SIX-BANK PUSH BUTTON SWITCHES each bank 4riim dia. u lImm. 10p each. all £1.75 each 4.000MHz HC6/U £2.00. 7.000MHz HC6/U £2.00. 6 peo. Self cancelling £1.00. JACKSON TETFER TRIM MER Cat No 5640 9mm. HEWLETT PACKARD PIN DIODES type HP5082- sq base. 25p each. also 8mm PC mount. 259 each BARGAIN BOX of P.C.B. this contains damaged. 3080 50p each or 4 for £1.50 PLASTIC SEMI-AIRSPACED TRIM MER as used broken. or incomplete car radio boards, hundreds of PYE COILS 5mm dia lOrnm sq base OK for rewinding in PVC Westminsters PA stages 10-60pf. 15p each useful components etc, sold by weight approx 2Kg as used in all PVC R/Ts. 8p each 10 for 60p. 14;lb) only £2.00 plus postage £1.25 (U K only)

59 WAVERLEY ROAD, THE KENT, RUGBY, WAR WICKSHIRE

Primed in Great Britain for the R AINO SOCIETY OF GREAT BRITAIN. 35 Doughty Street. London, WO N 2AF fry E T Heron it Co 1.1d. Eses and London